Probably the city of shelves. It's a city home to the largest shopping center in the world. Drones made by long since vanished inventor collect junk that rains down outside the city and put it up for sale within the city. Nobody really knows how big the city is since it's larger on the inside than out, and the shelves go on seemingly forever.
Edit: The reason for its out of control size largely comes down to the fact the drones have been engaged with the last command from their creator for so long that things have gone haywire. Drones sometimes act irrationally, and there's entire segments that are unmaintained and unlit, not even being recognized by the drones as part of the structure.
Thanks! The initial idea of a large space made of seemingly endless shelves of items came from a dream I had.
It slotted in almost perfectly with the existing junk heap area I already had in the world at the time.
It's since ballooned into one of, if not the most important location in the world I've made just due to it's implications
it has so many uses narratively too you could use it to give a character a new tool, sent them there for a hunt maybe, it also has such a ambience that is very unique i love it, maybe some drones are malfuncitoning and you would have to fight them?
Except, instead of being a place you can no clip into it's a location people visit to search for stuff.
My whole world draws from surreal media like Yume Nikki and Antichamber.
Same. Originally the world was just a giant Edifice with Antichamber like gameplay but expanded to be a world with physics and space that doesn't make sense.
Spaces being bigger on the inside than outside is not limited to just the city, it's just how things are for the people.
Allot of my world could be classified as anomalous. The junk plains and city of shelves is more fleshed out than other areas at the moment though. Since you can find just about anything there people come from long distances to shop around.
A short stay in hell has similar concept. It makes the reader feel so insignificant and out of breath. I really like your idea too. (◍•ᴗ•◍) very intriguing!
I don't really have a definitive timeline for events. If I had to guess, hundreds of years of expansion, renovation, upkeep, etc. The creator of the drones made them with the idea that to accomplish their task of collecting and selling items they would learn to innovate and adapt over time, so I'd imagine things got easier and easier over time as their tech expanded and more drones were made.
I had more of a antique/thrift store vibe intended overall. Very warm lighting, with tall shelves full of random junk. In the unkept parts of the city, items sometimes move on their own, and some shelves extend farther inwards than they should.
The Ananse have a partially completed Dyson Sphere around their host star. Ananse names don't translate well into human language so most of humanity just call it "The Sphere". It's primary intention is to provide energy for science project but also serves as a nuke dampener and laser array, essentially vaporizing anything in the solar system the Ananse don't want there. Unsurprisingly, no one has even tried to attack their home world.
The Enlightenment Project. A massive ai hyper computer constructed into what was once the Himalayas. Built to save humanity from a total climate catastrophe, it was effectively an artificial god that took requests like some combination of ChatGPT and the Monkeys Paw. It was instructed to save earth from apocalypse, and it did so by removing all traces of humanity actively harming the planet. Just deleted. However, due to either a deliberate choice, a coding error or hardware failure, it forgot all but one detail about humanity. Humans had no exoskeleton, and were not insects arachnids or arthropods. This resulted in every species other than the 3 groups previously mentioned being deleted as well.
The Monoliths.
Known more officially as **Large-Planet Deep-Cities**, Monoliths are super-structures built nearly 500km into the planet's core to harvest raw materials deep below the surface of the planet and housing the billions of people within them. These same cities also climb nearly 1500 meters tall, looking out over the vast horizon for miles around with towering skyscrapers. The entire structure is suspended by super large and powerful magnets over the planet's outer core.
The reason for their existence was because of a near-apocalyptic event that had occurred with the eruption of the last super volcano on Arius. Blowing its top, this thousand mile diameter super volcano exploded in the mid-3rd millennia, spitting trillions of tons of ash into the atmosphere and wiping out vast amounts of life and food resources.
Humans retreated to cities and what followed was a necessity to grow and survive in this now cold and ashen filled world. In time, these cities expanded downward to make room for more housing, industrial zones, and vertical agriculture farms to support the population. In the year 4323 P.E, 99% of the world's population exists within these cities. Crime is high, education is low, and people in all classes are just barely surviving.
The Stratower is the largest skyscraper in the known universe.
There are colony starships larger, but nothing terrestrial.
The Stratower is the size of a city, and its pinnacle is a spaceport that protrudes above the stratosphere.
My brain immediately went, "Wait, that sounds like it was word-for-word ripped from my favorite sci-fi books."
And then I read your username. I absolutely love the Torth series! The depth of your world building + the sheer unique nature of your characters makes the books impossible to put down. I've been on a sci-fi binge for six months, and Majority is my top favorite out of over a dozen books. The way each book mixes mystery, scifi, fantasy, action, and dystopia fills my soul, and I'm genuinely sad I binged them all so fast.
I have a timer on my desktop counting down until Megacosmic Rift releases!! Thank you for some of the best books I've read, ever.
The Mail Tower, a roughly 100 metre tall structure that acts as a central hub for the postmasters guild. There is much dispute over whether the Mail Tower is a single building or not. This is because there are several Mail Towers, yet only one of each of the rooms inside them. For example, if someone in Kuvshinka and someone in Dragoskala were to go into their local Mail Towers at the same time, they would meet up on the first floor lobby, despite entering from cities several miles apart. This is yet another reason why the Postmasters so thoroughly control the mail, as the Mail tower allows them to remain centralised while still dispersing their influence as far as possible. However the Mail Towers are not without flaw, as they only exist in the four population centres and cannot effectively deliver mail to areas distant from these three cities. It is believed by many that this flaw is why the colony of Slavaduyn perished.
The Great Mount is a mountain fortress that was raised by the gods (who are humans masquerading as gods so it *is* man-made technically) in the wake of the First City’s destruction at the hands of the betrayer god. It served as their stronghold in the mythic Dread War against this betrayer.
It looks *almost* like a mountain, only it’s too steep, and *far* too tall. So tall, in fact, that its peak pierces the earth’s atmosphere, and the palace of the gods is immersed in the perpetual gloom of outer space. The supposed saviors of mankind live in a place devoid of both life and light...
The Great Mount is surrounded by the Chasm, a crevasse that surrounds the fortress like a massive moat. A half mile across and so deep that no one can see the bottom. Some believe that the Chasm wasn’t made to serve as a moat to protect the gods, but that it was carved out by the Betrayer himself. That he had sundered the earth to set free the million million demons of hell to fight for him against his divine siblings in the Dread War. Whatever the case, no man who's attempted to cross the Chasm has ever returned from the bottom, so who’s to say hell itself doesnt lie at the bottom
Naryil's Capillaries are man-made by technicality, being a tunnel network dug by a biomechanical drill. Its original mission was to connect two of Ardeia's undercities together as a vanity project, but was left unattended by humanity for millennia and has since looped over itself uncountable times. It stretches below a 500-km length of the Hunchback Mountains in the present day, with local traditions honoring it as the road to the underworld.
Doya-taj is a more contemporary 200-meter tower built by the Lajean Empire in their efforts to expand their wyvern riders' effective fighting range. Overlooking the vast Nawasu Steppes, Doya-taj is the one and only spot along the frontier that wyverns can comfortably roost and recuperate between sorties.
The World Trees, gigantic space elevators connecting Duna to the Ring. The biggest one, Yggdrasil, is only slightly bigger than Olympus Mons in diameter and a few million kilometers in length. Long enough to extend past the orbit of the moons.
I haven't solidified everything, but it's probably either a palace or an armoured airship. Both kind of explain themselves. The airship probably has more of a *need* to be bigger due to requiring the buoyancy, helped by a thicker atmosphere. The largest ones are built by the southern empire and have various roles from transport of troops, supplies and vehicles to extending clear radio signal ranges to providing aerial power projection (including artillery fire and sometimes launching planes).
Lapis_Wolf
The Great Wall of Gryll (I know, unoriginal name) was built by the Gryll Empire for defensive purposes. Primarily it's meant to keep the Wildings out, with mixed success. (Wildings are eight-foot-tall, horned, furry walls of muscle who are exceptional at climbing.) It stretches a couple of thousand miles along the western border.
Largest “man”-made structure would be the Golden Goose Casino, simply because it’s so big half of it has to be shunted into SEVERAL separate pocket dimensions to fit everything….it’s basically it’s own country with how much it has
Depending on the context, but I'll go for tallest since the largest structure in my world is either a warehouse or some giant dam no one has heard of before
For some context, within Ahikto, starting in the mid 2000s, there was a large "skyscraper boom" which lead to the construction of nearly 100 buildings taller than 300 meters across the world. Most of these were located in the newly established capital city of Temugin.
The tallest building is, funny enough, still under construction but has long surpassed the tallest building in height.
**Kishinato Tower** is 1,347 meters tall. A weirdly specific albeit consistent number. This building has been under construction since late 2017, and will overtake Daxiang Tower at 1,140 meters tall. Kishinato Tower is the third to last building to be completed within the Kishinato City World Trade Center, with WTC 11 and WTC 13 still in the planning stages as there are buildings on the site that would need to be demolished.
Kishinato Tower also, funny enough, is going to be completed soon. Its expected to finish construction in Late July this year and open the public in early September.
(Fandom Link since I haven't migrated this page over to the miraheze wiki yet)
[https://ahikto.fandom.com/wiki/List\_of\_Buildings\_by\_Height](https://ahikto.fandom.com/wiki/List_of_Buildings_by_Height)
Define "manmade". If you mean made by humanity, they're the Passes built by Atreisdeans. Such Passes are 20 megameters across made to connect two ends of an Einstein-Rosen Bridge (or in layman's term, wormholes) together and stabilize them enough for large fleets to move through. Spaceships move in large formation so they won't accidentally crash on each other because gravity works funny inside the tunnel. In extreme case, they can yeet **entire rocky planets** through the Passes.
Largest artificial structures belong to L'Aurelles, a race of space jellyfish-men transhumans. They build enormous biomechanical Dyson spheres called Vor'toms around stars to absorb photon, which is their primary "food". Vor'toms can control gravity of their own, affect a star's spinning speed, and can **drag them along**. There was a case a L'Aurelle colony departed and they took their Vor'tom, with a Sun-level star inside, with them.
There's a reason why Atreisdeans, with their system-erasing time-travelling *common* weapons, don't want to anger L'Aurelles.
The City of Kelis is the largest manmade structure. It is carved out of the bottom of what was once the largest mountain in the world. It serves as the hub for the largest religion in the world, around half the population of the city works directly for the religion, and the rest work in roles which support it.
Scattered across the main continents of Dorowhen are enormous towers (about 450 feet tall) that can be best described as structures of cubism architecture made out of crystal circuit boards.
These are the Geospires, a remnant experiment left from the days of the Primarch Empire who used these continents to test out potential terraforming technologies. Each of them creates and actively maintains a constant environment in about a 200 mile radius, and are the cause of the strange climates found only in this region of the world.
There are currently three known Geospires in the world. Cryospire, which creates a frozen tundra quote close to the equator; Dessicant Spire, which created the Kelsan desert (which has been slowly spreading and threatening to desertify the rest of the continent); and Verdant Spire, which created the jungles of Istulra where the Beast Folk (another large scale experiment left behind by the Primarchs to give animals sentience) make their home.
Fantasy: The Catacombs of Nahm, a vast underground complex that houses the remains of desert God-Kings long past, as well as their relics and other valuables. The catacombs span the majority of the western desert.
Sci-fi: The Rift Engine, a massive machine using advanced extradimensional technologies that is being constructed in the cyborg-claimed desert. Its true purpose is unknown to the world at large, but it has been theorized by one rogue cyborg who has absorbed a piece of the material that it may be an attempt at either immortality or a wormhole generator.
The larges artificial structure is the setting. It's a Birch World. It has more living space than whole galaxies. If you traveled around the equator at 10,000 miles a day, you would take a paltry 6 million years to complete an orbit. Also, it's so large and heavy, escape velocity is basically 90% of the speed of light... so no one has left since long before it was finished. It's also old. It was finished so long ago that stars were still burning. Now even the youngest of red dwarf stars has burned out leaving the universe outside of the Birch World dark and cold. But inside, life thrives. Each level of the structure plays host to one of the races that helped in it's creation, though now no one is sure how many levels there are.
The largest known structures in my sci fi world are these mega structures called “Galactic Forges”. They were used by the Ancient Ones hundreds of thousands of years ago to build new stars and planets (even entire solar systems if they wanted) to how these demigods wanted. They were spherical and its width was 2.8 billion miles which is the orbit of Neptune as a comparison. From what archaeologist decoded of the ancient one’s complicated language 12 were destroyed with 1 remaining uncounted for so it could still be out there.
The city of Aurora, humanity's first great step into the stars. It's this enormous interconnected city that contains examples of every architectural style in history. The old city, now the undercity serves as the foundation for new construction and many of the buildings there have been completely filled with concrete for this purpose, the poor down there will carve pueblos directly into these concretes facades. Everything is so densely packed and every space is used. High above, in the peaks of the city the buildings are sealed because they're so high that air needs to be supplied. Aurora is 12 citied stacked on top of each other, each more advanced and lavish than the last. A continuous construction of skyscrapers and towers for more than 1400 years.
There is a series of underground bunkers, laboratories, and military facilities that are connected by high-speed railway tunnels below the United States. It is known as the Mycelium Network. It started as separate facilities that were constructed in the 1940's, 1950's, and 1960's. In the 1970's, they began construction of tunnels to connect them and the high-speed railway system officially began operation in 1986.
New tunnels and new connections were being built throughout the years right up until the Nuclear War of 2029. The Network got so large that is was possible to go from Washington, D.C. all the way to Nevada and California completely underground.
The purpose of the network was so that the U.S. government and military could continue their activities in the event of a disaster. It also served as a convenient transportation system to transfer clandestine items from one facility to another without drawing significant amounts of public attention.
Depends on how you define 'large' - if it's something like sheer coverage, that would be the Lycadian Food Pyramid...I'm pretty sure there's no existing structure on Earth whose foundation covers half a mile in every direction.
As for its purpose, as its name suggests, it's a giant arcology-esque greenhouse.
There's a massive wall of some strange alien metal encircling the entire northern sea. It extends from the sea floor to just below the surface of the water, and it glows with mysterious runes in no known language. Massive electrical storms and strange auroras dance in the sky above it, and St. Elmo's Fire flickers across the masts of ships which venture too close.
No expedition has ever managed to cross this wall and see what lies beyond at the planet's north pole, but rumor has it that the wall guards an ancient, technologically advanced civilization. The land beyond the wall crops up a lot in fiction - it's kind of like this world's El Dorado or Atlantis.
In truth, beyond the wall is just a barren, icy sea. The real ancient civilization is within the wall itself. Unbeknownst to the people of this world, the wall is actually a huge, ring-shaped spacecraft which ancient humans used to travel to and colonize this planet.
If you stretch the definition of 'structure' a bit, then the grand archipelago is the largest. It's a collection of naturally occuring floating islands held together with man-made bridges and chains.
March of Empires has Galactic Rings. Enormous structures surrounding the boundaries of the galaxies under human occupation. These are located on the Galactic plane along the entire boundaries of the galaxy. They have swarms of pure energy-made USVs, also called Unmanned Space Vehicles (E-38 and E-39 are the units in Operation on the Rings). These serve a multi-purpose role: Fortresses to launch defensive maneuvers from, and the use of the drones to map and locate potential sources of energy. Intergalactic trade also happens often through this sector. It is Enormous, lightyears long. Their defensive systems are some of the best, including Intergalactic Sterilization Sniper Cannons, Stellar Rays, Statofortresses, Stellar Phantom Bombers, Bullet-Class Cruisers, Hyperspace jammers, Universal Communication Jammers, Imperial-Class Destroyers, and Cybertronian units. Entire armies can be launched from it: made out of Stellarium, which stays at high temperatures, Galactic Rings are flexible and can open doors almost everywhere. Everyone wears heat suits and consumes coolant drugs to keep themselves from burning alive. The power required to destroy a Galactic Ring is equal to the power required to destroy a medium-sized galaxy... so a civilization needs to be Type-3 with similar military power to achieve such a feat.
Arguably, the setting itself.
So many things need to go *right* for the Skyring to exist that natural generation seems unlikely. Its not *impossible*, mind you, but is almost certainly unique in the galaxy, if not the universe. If the star is too big or active, the gas ring won't form with hospitable pressure. If the gas giant lacks oxygen, that gas won't be present in the gas ring. If the gas giant was any closer or further to the star, the sky ring would simply fail to develop in a stable configuration.
Combine that with Builder "Temples" that seem to do... something in regards to the Skyring, along with enough advanced technology in them to suggest that stellar body manipulation wasn't necessarily out of their league, and there's a good argument to be made that the Skyring might be some alien experiment, art installation, or the like.
The Tower of Babel still remains the tallest building ever built, being approximately half a mile taller than the Burj Khalifa. What happens when humanity once again is able to reach those heights? ... ...
In the future, a giant space station was built that was only a little but larger than the moon. Like the Death Star in Star Wars. It was built as a way to transport to other planets in the solar system for terraforming.
My world's whole gimmick is that humanity had to restart mostly from scratch after most of civilization left for other solar systems.
There was a secret society that was left with all the technology humanity had before they left, being the most advanced civilization. After the man made moon was not in use anymore, the secret society planned on using it as a beacon to signal the rest of the humans in the sky to come to earth. They would send a giant laser up in the sky, hitting the satellite, then it would refract and spread the laser throughout space so then they can hope they would come and save them.
Hell's gate. built hundreds of years before the Storm of Light, the 50 mile high volcano fortress stands as testament to the supreme power of the early demonic lords, its solitary tower sits on its obsidian slopes, now the only known part of a once feared fortress, it is one of the worlds largest castles In it's own right. the entire volcano is at present being mined by elves, as the magically mutated evil gold ( or De Nyryngyld if we're speaking modern Tymori) can be used to create wmds.
The Pendula. They were constructed before the Schism, as a way to evacuate large population groups at once. Essentially they were massive elevators, bridging several continental land masses with Planets. Of the three planned, only two were completed: First Elympos, which was connected to Earth, and the Broken Watcher, which reached to Mars. It is largely unknown where the third Pendulum, called the Pariah, was meant to send wayward refugees.
First Elympos was successfully activated, with evacuees documented in the tens of millions. The Broken Watcher, on the other hand, was met with failure. The tower’s mechanisms suffered crippling faults when Daluvimenrais burst through the rift between the world and his prison in Trolos, which invoked the Vestige of Floods and triggered the Schism, thrusting the Planets from the sky and into another dimension. Any lives that reached the surface of Mars are believed to have perished in the impact.
All three Pendula stand as looming ruins casting their long shadows over the civilized world, people having long forgotten their purpose.
Currently it is the Grand City in the Azron Valley in the nation of Kyzanta, which is essentially just this bigass pyramid. Unfortunately... this structure was not made by man - or even any currently living races for that matter, and gives more questions than answers. All I can say is it's currently used as a tourist trap in recent times.
The current largest ~~man~~Ketuvyx-made structure is the Allocator, which is a facility on ~~Europa~~ the ice moon of planet 5. Its purpose is to receive starlight from a distant, abnormally bright star via breachgate satellites and, using a clever setup of lenses and more breachgates, condense the light into beams for whatever use is necessary. That could be using some to generate usable power, or it could be focusing raw starlight through other breachgates for use as weapons. It's currently the size of a small city but is planned to be expanded until it covers the surface of the moon (along with more collection satellites launched).
Looking at the broader setting, a ecumenopolis from one of the older species may count.
In the far future of the setting that's ill-defined I'm entertaining the idea of the Ketuvyx Ascendancy constructing a Birch World, and maybe even beyond eventually.
In the world of Solaris.
The Floating City of Titan: Anchorport
A massive city built from hundreds upon hundreds of ships. Thar have been Frankensteined together. Explorers, adventurers, researchers, pirates, just about anyone really, would make their way to the archipelago controlled by the Titan Empire hoping to strike it rich in the under water labyrinth known to be one of the Graveyards of the Gods.
Areas of Solaris where the gods fell and their corpses warped the landscape, civilations fell and monsters began to lurk. Treasures and resources ripe for the taking, and a lost history waiting to be unfolded.
Over 1000 years of ships have stayed behind as thousands lay there below in the underwater grave, though a curious clan of shipwrights always maintained the ships, hoping the explorers would return. It became so packed that the ships began to be built together from the confusion of maintainence. Those few that did return, usually, empty-handed, would find their ship melded with another. With no way to return most would stay. And thus Anchorport was created.
Elas itself is a massive artificial world currently shaped like a bowl with six arms stretching towards the sun, though I'm considering other options atm. It was built by technologically/magically advanced race from another reality who act as guides and protectors of the mortals.
Inside Elas the largest structure is the Forgespire. A tower standing a half mile above the desert sands, and extending just as far beneath the sands. At ground level then Spire is a hexagon covering approximately half a square mile. The Spire is home to the bulk of the race of clockwork constructs known as Forgeborn.
one person had made a maze, 100 by 100 km. it is called the splitted maze, because in the middle is an open place that is splitted into 2 places where two groups of people lived. it is so big because the builder likes to be famous and must have a place to put some dangerous monsters in. the monsters can't solve the maze.
The Castle-Complex of Gurenthan. Larger than some countries, has survived being attacked by the god of death himself at full power. Is also the oldest because it just survives apocalypses .let me know if you want to know more
Old Engress is an abandoned underground city that traces its origins back to a gold rush in a region filled with dangerous fauna. A massive series of mysterious underground caverns were discovered in an untamed land, filled with valuable ores, rare gemstones, crystals, you name it.
When those caverns were discovered, the continent was under the thumb of a great emperor who dedicated vast resources to tapping its riches, kicking off a golden age.
Great beasts and monsters inhabited both the caverns below and the wilds above. Townsfolk often holed up in the mineshafts. Bunkers were built for emergencies, and those eventually became permanent residences. The whole town moved underground and as the massive caverns were mined out with no end in sight, the city expanded beyond reckoning. It was resplendent and exceedingly prosperous, with roads lined with gold and jewels.
This continued for about a thousand years, the caverns seemingly unending. Old Engress became so large and porous from mining that it was largely indefensible. In the meantime, the surface had been long tamed for living and agriculture. Old Engress was hastily abandoned for the surface following a collapse that overwhelmed its defences against the deep.
Engress sits above the abandoned city, and its mining operations have turned to scavenging the abandoned riches below. Old Engress teems with dangers and the caverns below it are largely considered lost to the creatures of the deep.
The Arks. Five were created to save the world's population from imminent cataclysm. Only two returned to the now shattered planet. One was lost to gods know where, one was besieged by aberrations in space and is now a danger zone where no one dares travel, and one fell in the ocean.
(All characters are the work of fiction here and not to be associated with real persons!)
The Capital of the Galactic Commonwealth, and its Royal palace. When the Brits colonized the LaCaille System in 1971, her Majesty the Queen and the British Nobles demanded a new Palace for the Royal Family on the new capital planet of Ashworth-336. The construction began in 1972 and was nearly finished when the news of the war on Earth interupted the whole project. The evacuation of her Majesty and the royal family was an utter faliure and almost every family member had died after their shuttle has been hit by a raiding party. Only the Teenager Princess Anna II had survived, and was mortally wounded. When the shuttle was found by the United Colonial Space Forces, the princess had been aided and escorted to Ashworth where she became the new Queen of the Commonwealth, and finished the royal palace after a year and a half mourning her family.
She demanded the palace to be bigger than ever… to be the biggest building mankind has ever seen. To be the shining Jewel of the new Empire, a tribute her fallen family, to the Queen. With that, the palace has been finished by 1986, a neo-gothic, multiple hundred story building decorated with more gold than the entire gold reserves of old earth ever had. This is where her Majesty Anna II. and her government rules over the Galactic Commonwealth.
There are a couple of different answers. I have a list of natural and constructed wonders of the world and a few of the constructed items stand out.
The longest structure is the Imperial Road in Faras, a large central road that is heavily barricaded by ramparts made of obsidian. Stretches the entire length of the kingdom. In the distant past a king now known only as Lofelk the Strange basically ended his rule through the madness of this project. The unholy amount of labor required combined with a lot of people not being compensated at the end caused an uprising that dethroned him. No one really knows (I haven't come up with yet) why he commissioned it and why he wanted it to stretch the entire length of the kingdom (even past the last major city in the far north to reach the barren coast).
The most massive is a large bridge that spans a large sea that connects two twin capitals, Egrin Lilith and Drus-Tirith, as they represent two kingdoms that have combined. An elven kingdom adopts a population of halflings that had to abandon their original home. They give them some land and help them build a nice city. The bridge is supposed to be a physical representation of the connection between the two peoples. And it's big because the sea is big, lol.
If this would count to you, the most voluminous is probably the caverns inside Forak-Khagal, the capital of the main dwarven kingdom. A large fissure in the ground in polar ice is populated by dwarves who have many structures built into the walls of the fissure that lead to a large and elaborate underground city. And it's big because dwarves are cool like that.
Well, there's a lot. Black holes a lightyear wide, trains that cross between galaxies and even galaxy clusters, and of course the giant resource hoard they build after all the stars die out, made from all the galaxies they could bring back home at under the speed of light, so it's basically the size of a galaxy but way more dense and has tons of connections between the various nodes. Yeah, my world engages I megastructure engineering constantly, to the point where dyson spheres are just a given and are viewed as like setting up a tent for camping. In fact even back when they had only colonizedthe milky way they had more dyson swarms than we have people (400 billion to be exact) and now they have 120 billion galaxies just like that, though only a fraction of that was incorporated into the primary hoard.
Bastion Station was built by the Architects at least 72,000 years ago in the Astra Galexy. StarCom found it in 2003 along with the other structures. While the Architects build larger things like Dyson Spheres and Ring Worlds, the station was the largest still standing after the Relic Wars. Most archaeologist believe the Architects built the station just because they could as some from of challenge. So far only 20% the station is inhabited due to a mix of archaeological excavations, critical repairs, and a simple lack of people to inhabit it.
The Library of ancient runes, relics, and scrolls
The library has millions of scrolls its seems to reach the gods because it almost reaches the clouds.
It was made with elven wood, Dwarven nails, titans strength, and humans math.
It's used by God's and goddesses alike, to learn ancient magic this is where you will want to go.
In my story I made the main protagonist named Mizuho had gone here and stole the bow & arrow of the Nature God.
Many relics are held here, I will some of list them off
• the staff of judgment
• the daggers of lust
• the sword of hatred
• the axe of pride
Each made bye God's and blessed by the creator.
Out of all the megastructures humanity has built, Dyson spheres, massive habitats and gateways, entire planets converted to warships, massive vessels that serves as a city and a spacecraft at the same time as a mobile Spacedock, all pales in comparison to the Avalon class of ring worlds.
A massive loop at over 10% of an AU Wide, each station is indestructible, and is home to trillions.
Equipped with enormous defences and many stations, along with a massive shielding system, only three of these titanic ring worlds have been built so far, with no plans to build any additional ones
The Front Line.
So when the apocalypse happened, it caught the precursors with their pants down in the middle of whatever they were doing. In this case, they appear to have been fighting a massive war. It's unclear what this war was about or even who was doing the fighting, but its remains are still there seven hundred years later.
The Front Line is two lines of miles-deep fortification lines facing each other across a no-man's-land. Behind these lines are miles upon miles of artillery positions, command posts, and logistics depots. Mountains of rusted spent artillery cases tower into the sky. The line is so long that it bisects the entire continent. While not necessarily the largest structure, the Front Line is certainly one of the longest in the Underscape.
While the war is long over, the Front Line is still very dangerous. The automated defenses still appear to be mostly online, and mechanical monstrosities still roam the deserted trenches and bunkers. Landmines, unexploded ordinances, and other traps litter the scarred landscape. Traces of poison gas still infect the air. However, all of that pales in comparison to the true terror of the Front Line: Netwire, one of the worst surviving creations of the precursors. Netwire is mechanical razor wire that can move and appears to be somewhat sentient. Netwire hunts those who wander into its territory like a predator, striking quickly from underground and dragging its poor victims into the mud to do God knows what with them. Since Netwire cannot eat, it is theorized that it hunts for pleasure. The infernal wire has even been known to use the bodies of the dead like puppets in order to lure in new prey. The Front Line is absolutely infested with Netwire, and that is reason enough to not go anywhere near the place.
Those who have seen the Front Line are often left with profound sadness. What sort of monstrous hatred could have inspired such horrific weapons? Whoever the precursors were, perhaps it is best that parts of them remain buried.
Technically, it's not man-made since the Ancients built it, but the Observatory is the largest single structure ever built. Its foundation is on some backwater elven farming world, but it extends out into the void between worlds. Because it isn't in conventional space, its height is technically infinite while still being finite. It is not recommended to look up at it from the ground. The sight tends to induce extreme vertigo and an acute sense of insignificance.
It's purpose is to take advantage of the observers' paradox on the macro scale in order to tie the worlds together and keep their clocks in sync. Without it, trade between worlds would be impossible since a traveler may arrive at their destination hundreds of years before or after they left. The Observer is magically tied to its massive sensory apparatus and can use the multitude of sensors to observe anything under its aegis.
I think that would be the Truesilver Tower. Not quite sure though, I would have to go and measure.
The most important building in any given elven settlement is always a tower - for cultural reasons. And the really big or important towns and cities are built \*as\* (or converted to) towers and always expanded by building another layer upwards. The White Tower, the center of elvenkind, was such a city. After a cataclysmic war at the end of the last eon, the center of elven culture and nexus of magical prowess on the continent had been razed. As a sign of gratitude and eternal friendship, the dwarves of Dragon's Maw shifted their still running war time production from arms and armour to building materials and went west, to rebuild the lost elven tower. With their mines and workshops working at peak capacity the dwarves were able to invest vast quantities of mithril into the construction project. The result was a tower double the size of the original which was seen as basically indestructible and renamed to fit its new coruscating appearance.
You'll probably never lose your way when you try and visit the elves in their tower. It rises high above the trees of the forest and seems to be tickling the clouds.
The Saffron Lifewall is an enormous dam with a huge complex of integrated mills. It got its name because laboring conscripts engaged in work stoppages, driving the project behind schedule. As punishment, the Emperor decreed the locals would cover the complex in a costly color of paint, at their own expense. The region seemed headed for severe economic hardship, but within a generation it instead became a thriving center of industry. Now locals keep that eyecatching paint in good condition as a beacon to traders and travelers keen to part with coin at businesses around the Saffron Lifewall.
The largest human-made one was the Global Climate Control Grid, a massive orbital structure connected to the planet by several space elevators that consists of several rings, hundreds of stations, and untold numbers if smaller satellites to precisely control the earth's climate and act as a sort of "hub" for Interplanetary travel.
Sadly it didn't last long, collapsing to the surface after only a century due to unknown reasons.
If you count other species well, the city Planet of Ahs'Jutan would be one.
A planet 1.5 times the size of earth, with over 80% of the surface covered in several Kilometer thick urban sprawl and industrial complexes. A marvel of engineering created over millenia.
At least, until the planet gets glassed.
Probably the World Tower Zranta. It was build in the first World (context: The ancient gods made a world, then later disliked it, destroyed it, repeated that process with a second one and then the third stuck). It's a tower reaching to the sky. The gods said to them that if they build this tower they will be blessed with a power that could rival the gods. So they began construction. After a while many people fell off the tower and died. One Guy did not like this whole thing so he went to the woods and found a "wizard" wich was one of the gods in disguise. He taught that guy magic. Before this no one could cast magic. Now the guy helped constructing the tower with magic. They reached the sky not long after and a light appeared. The light said: ,,You people did it. We grant you all the power that was found by one of you". The light granted all of them magic powers. Maybe not power that could rival the gods but the people thought it could.
The whole thing is also inspired by the Tower of Babel Story
The Dam. Yes, there are smaller dams but this is the largest infrastructure project on this world (which happens to be a parallel Earth in which a different strain of Homo Sapiens won out).
It is the equivalent of Hoover or Glen Canyon Dam on the Colorado but located in original time line Colorado in Glenwood Canyon. This is were I-70 in Colorado has some of its best scenery.
Here most of the water from the upper alternate Canyon River (our Colorado) are diverted into the Greenland River (our Rio Grande) to supply the large cities and farms centered around the interdimensional gates found near the Cracks (the Trinity Test sight).
The largest city, Gypsum Field, is near our Truth and Consequences, New Mexico and houses around three million people. Sapiens B, as people of a timeline close to ours has labeled them, tends to have more dispersed populations.
Probably Ares colony on Mars. Its set of 5 domes biggest one being around 3km tall and 6km in diameter constructed with lots of internal supports that work as living apartments as well, there is also central Spire building housing atmospheric control center as well as nuclear reactor that provides most of the dome's power. At current time in my universe it is biggest structure possible to be built
**The Gardner**
I dunno about "man" made, but it was definitely made and altered, it is a celestial body that generates heat and light as well as a barrier between its domain and the rest of the cosmos, separating space that falls under it's own dominion and laws from the influences of beings beyond.
The single biggest building in the main nation (I haven't really figured out how things will change in the other nations) is Te Whare Hui o ngā Kōmihana (Meeting House of the Soviets)
Think of the Palace of the Soviets (canceled replacement for the Kremlin in the 1930s) but instead of being designed by one soviet architect on meth, it was designed by a team of architects that took the whole project seriously instead of one giant propaganda show.
784 Meters tall (minus statue) it is a multi-tier kind of building, similar to how the Burj Khalifa looks but more symmetrical. Built-in the dominant architecture of the country at that period (think a kind of Utilitarian/Brutalist Gothic fusion), The bottom tiers are made out of Stone (Basalt, Limestone, and Granite), while the top parts are the usual mix of glass, concrete, reinforced steel and some lighter stone on the top.
The building serves as the location of this Country's version of the Supreme Soviet, White House, and central government office all at once. There are positions amongst the higher floors where CIWS-type devices can be Mounted, as well as a sprawling underground complex that serves as a bunker/command room for the Central Government but is also the headquarters for the OSRI (this country's intelligence service)
This is never likely to be used, as due to a previous attack that wiped out the meeting house's predecessor as well as the city it was in, a massive air, land, sea, and space defense program was initiated, and the entire, now rebuilt city is the focus of that (not only due to the meeting house but also to protect a series of Portals that connect this half of the country to its other half, situated in an entirely different universe.
The top of the tower is home to a statue, this universe's version of "The Motherland Calls." It is a 100-meter-tall statue made from Unique Minerals and rocks from every SSR. The statue depicts a Woman with a feathered cloak and a Zweihander-style blade pointing toward the Ocean.
The Flat space on top of every tier is a mix of Garden and outdoor art galleries, with several statues and exhibitions detailing critical battles, events, and moments in this country's history.
Megalopolis of Startess. Startess is an enormous city nicknamed jigsaw. It's tightly packed with illusions of wide open streets, making it appear to look not as condensed as it appears. It's so big that there are entire sectors similar to towns/cities taken over by gangs cause what's there isn't worth the cleanup.
The *Kø̀brik mon Rapat* (Bridge of Swords) is the largest structure on Zùvà Arìànuh. It's a suspension bridge that crosses the Strait of Swords, the entrance into the Great Blue Bay on which sits the world's largest city *Korat Bàkalif Kanalø̀* (pop. 720,000 as of ST1020). Constructed between ST0072 and ST0073, it's just over a kilometre in length, its two towers reach 302 metres in height, and it's painted a pleasant shade of blue.
It links the city proper with the commercial harbour district and northern suburbs. The upper deck carries foot and cycle traffic with a lower deck for light rail, freight and emergency vehicles.
The bridge takes its name from the strait, which in turn was named after three rusted swords of unknown origin that were found at the base of its southern cliffs by the first survey team to visit the area (they now reside in the city museum).
The bridge is regarded as a symbol of *Korat Bàkalif Kanalø̀* and appears prominently on the city flag. Locals are generally pretty smug about it being over three times taller than the next tallest structure on the world, the *Oliskuh Konsòtium* in *Korat Balzad Zùvàrùn*.
The Wreath.
An “orbital ring”. A titanic international space station circumventing the entire Earths equator, located in low earth orbit.
It has multiple purposes, but it main one is being a jumping off point to space. It has a multitude of space elevators attached to it around the globe, and acts like a combined launch platform, dockyard, habitat and transport network.
The Black Book of SRL (Saral) is literally a giant stone book with the entire (equivalent of) 7 bibles inside. Usually said bible (the Jilam) is split into ten books but the Black Book condenses all of them into a 50, 60ish ft tall monolith.
At the center of the dragon world is their capital city, and around the whole city is a giant facility called The Ring, which is a colossal building surrounding the capital city itself. It serves many purposes and is divided into different parts that serves different purposes, like a hospital part, a portal center and many other workplaces for the dragons.
I like to cram gargantuous stuff so ancient as to dwarf any character or their current era's architectural/engineering achievements, in my worlds, so there's something of a list... Not that I ever actually made a list or anything, so to speak, mind you.
I don't think it's so much amazing rather than me just going into the ridiculously sized, nor is it completely detailed, but: (PS: I'm being vague about the species/race/people because it's moreso a template of sorts which I adapt, like other world elements, to the settings I include it in.)
The largest I ever explored would have to be an entire, gigantic artificial world with a solar system harnessed within it. A pulsar star encased in a dyson sphere core at its center whilst the habitable worlds orbiting inside are cultural hubs and home to the society's elites due to the natural nature of the worlds and the scarcity of living space permitted on their surfaces, and other, uninhabitable planets, well, they don't exist as they have been exploited to their cores' marrow.
The artificial world doesn't really have a name, as it were, it's usually referred to as "the crust/shell/shield/surface's surface" or other such. It was built during a time when projections were made that nearby systems would be turbulent due to several stars would enter new ages or die in succession. To soak and reflect whatever would come the system's way.
Rather than protecting merely the habitable worlds as one would typically focus on due to resources, they encased the system as a whole due to their people habiting nearly all planets, at the time, whether on them or orbiting from stations that were vital at the time; as well as their people's overall deep galling spite. They simply felt like throwing a middle finger at the universe's ways in unison and laboured to achieve the impossible, even given their already advanced technology at the time - which the project's duration furthered, in a sense it was akin to a nuclear arms race during WWII.
Time after these dangers passed, the shell began being reworked to accomodate life, where the lower echelons of society would eventually be confined to. Those living in the natural worlds within are called low-lives by most crustlings, as a play on their position in the structure of the star system; and the elites similarly call those living on the shield low-lives.
The dual use may lead to confusing and awkward moments of camaraderie when two individuals complain about low-lives together upon meeting in a pub before realising they refer to one another.
Don't know what exactly counts.
A huge wall between mountain range and the ocean which was built by an empire to control trade, the migration and to protection against invasion. Originally the border were river but cities, but they grew too large on both sides of the rivers necessitating a new artifical border. It was damaged during an earth quake and then abandoned.
A City district carved into a mountain which over time developed into one huge structure instead of many buildings. The city was right next to dormant vulcanos and a river system flowing from the same mountains the wall was built. Due to the ashes the surrounding land was very vertile. The specific place of the city was originally a natural river crossing with a lot of trade.
"Razed" by invaders after being damaged by same earthquake which damaged the wall. Because Toxic minerals from eruptions linked to the earth quake plus actively poisoning the ground by invaders the city was abandoned and not rebuild.
There is also a long channel, farther in the south which was built to be able to create a new trade route from the western empire mentioned earlier to be connected to major cities/empire other side of the continent without going through dangerous arctic waters or a very long land route. After the fall of the great trade empires it became a border instead of a trade route.
I'm not creative with names, so don't have any names yet and called just by what they are. High distric of the capital of the first western empire, great wall of the first western empire and great southern channel.
Oldest _remaining_ manmade structure is a centuries-old military base, mostly buried under a desert. Infrastructure and engineering in my world haven't recovered enough to build skyscrapers and things like that
Depends on what you mean by "manmade"
If you mean specifically made by humans, the largest single structure is the ancient voidship at the center of the Capital, which is a whole city unto itself, especially after being build upon by multiple subsequent civilizations. I could also just say the capital in it's entirety, but that's more multiple structures in my mind.
If you count made by aliens, and you count careful cultivation and pruning to guide the growth of a giant mat of plants (or plantlike "animals" in this particular case) as "making" something, then the Noenlands. Literally an entire continent created through generations of massive scale projects, including building support structures to guide the growth in specific ways, like the megastructure equivalent of a lattice for grapevines.
And if you count gods, then the planet itself is actually a giant magical mechanism. The crust of the planet is pretty thin, and everything inside that is artificial mega structure, long since overgrown and abandoned, and now home to a whole subterranean ecosystem and civilizations. I think this kinda qualifies for the question since most planets in universe are naturally formed, this one just happened to be literally built and is actually a machine on the inside.
If we’re a bit liberal about “human” the world of Elysium (blessed home of the Gods, blah blah blah) is encircled by a single equatorial ring pierced by sixteen orbital towers.
We can be a bit less liberal and look at the Colonials. (Like most of the Elysians they are near humans but they aren’t ruled by posthumans) The colonials never developed FTL drives so when they realized their star was destabilizing they built vast colony ships.
If we’re strict about what’s human, perhaps the sixty kilometer dome protecting the city of Verneville on the Moon.
There's a space station that was built during the initial colonization of the solar system as the magitech equivalent of a fuel depot and later abandoned as technology advanced and people no longer needed to refuel in the middle of trips. A group of pirates took it over and, shortly before becoming too big of a nuisance to remain under the radar, decided there was more money in being Space Monaco than Space Port Royal, transforming into a haven of organized crime and vices.
During the chaos of the abandonment of Earth they expanded a great deal, buying the ramshackle ships most of the refugees used to get off of the planet for pennies on the dollar and turning them into thousands of new modules and habitats. Today - or, if any of my players are reading this, *the last you remember* - the population of Waypoint sits at a respectable 1.2 billion, making it effectively the third largest city-state in Human space, though it only accounts for around three percent of the solar population and a much smaller fraction of the total population of Humanity.
It's still more or less run by the mafia, though.
The Monarch's Visage. Appears to be a really, really enormous ziggurat with 4 towers on each corner, and a palace right on top. A city of the North is equal to 6 Earths in area, and this one structure's area is 85% of the central capital city (which is about 10% bigger than the other surrounding cities). Designed to hold in a hundred septillions' worth of people at one time, this structure is both the seat of influence of the High King of Karinia, a last bastion of the people, and a city in and of itself. Within the first 300,000 floors from the ground up, are living quarters, and farms with plants that feed straight up on mana and is safe to consume, and wyverns, a drakeborn livestock kept and eaten like Earth's chicken. Staple food of the North. 300,000 more floors have more living quarters, and a few hundred training grounds, half of which have forests in them. 400,000 floors right after those 600,000 are more living quarters (btw it isn't a chore to get in and out of a living quarter, portals exist, and those have basements for storage and is rather spacious, maybe as spacious as the area of a five star hotel), and an arena where blood can be spilled but no one dies. Sometimes the High King, the Kings, the High Lords, and Lords and generals would demonstrate new skills there for the people to watch. Btw this place has its own server, and yes the internet exists because it's been 5 trillion years when this building was completed, same with lasers and stuff. 200,000 floors of purely living quarters and some restaurants exist in at the topmost half of the third tier. The Red Throne Room, which is only used by the High King to sit around in or pass his judgement and pass laws, the Throne Room has no pillars and is vast, with light taking a second to bounce around in the room. Found on the middle of the actual palace's first floor. The Drakerest, which is where dragons being cared for by the High King are kept, is a floating tower with no roof (the usual towers you see, it has a turret but no roof) and many entrances the size of well, dragons. The right wing of the palace has the Monarchial chambers, a war room, a library, , some study rooms, and central server rooms. Out front is the Left garden, where herbs are grown, and can be used as a training ground or a place to relax. Has a lake the size 90% of an earth. The left wing of the palace has attendants' quarters, maids' quarters, butlers' quarters, chefs' quarters, an armory, blacksmith's, a forge, guest rooms, a massive feast hall, a weaver, and a tailor. There's also an orchard here and flower gardens. Both left wing gardens and right wing gardens have fountains and is essentially a park as well.
The four towers. One is the Martial Tower, where the greatest melee weapon wielders are nurtured. There's a floating fortress right next to the top floor of this tower as well. The other behind it is known as the History and Cartography Tower, where all knowledge recovered and records about the history, geography and what the world used to look like and now looks like are kept. Nurtures scholarly adventurers. The third tower across this is the Arcane tower, where everything magic is improved upon, studied, and new spells and runes are discovered. Is the seat of the Magus Ultimar, and houses the greatest mages in life and death. Last but not least is the Forge tower, where armors, mechs, lasers, and other usually militaristic constructs and items are made. Right below the entire palace are the Inexhaustible Mines, named for what happens after you dig out a single ore, ten more appear right behind where you got the ore. Favored dwelling of dwarves and kobolds; children of trolls and dwarves, outcasts in ogroid culture and society.
Ive been thinking about in one of my world having the dwarves hallow out an entire mountain to build a giant organ instrument in the mountain it is also the most complex instrument every designed it actually requires 3 people to play it and they have to be in perfect harmony its basically a one instrument orchestra
"Manmade" is actually the Gealtian Empirial Palace. The Largest "Elvenmade" are the dozen spires around the world that make the palace look like a fort.
The story takes place across several eras thousands of years apart and in each of these eras, one of the races called the Osyci have been building a massive, black wall across the entire planet. None of the other races know its purpose but the Osyci do not care who or what is in their path.
It will be built. If they mean for it to go through your kingdom and you take issue with that, you may fight them and you will lose because they will fight for an eternity if needed until there is no further resistance to the wall being built.
The white flame tower is 150m tall but it's only the visible part of a vast network of gaz and geothermal water covering the thousand Km of the Fallen Empire of Aïtsara. The goal of the structure is to provide power and heat for all citizen, industries and greenhouses. Some part of the network are millennia old and need a special engineering team know as the "Piper". The Piper are part of the army as some part of the network has fallen into wild territory and need some "killing" ability. If for a reason or an other the network suffer a critical failure the entire continent will became non suitable for life as temperature rarely go above 0°C. The Fallen empire is the most advanced nation as the rest of the planet is on late antiquity period (IV-V AD).
The tower of Babel. Actually a pyramid. The base [was] 5×5 km (3.1×3.1 miles), and it [stood] 3,180km tall (1.9 miles)
The tower was the final construction built by humans, dwarves, and giants as a collective. After its completion, around 4.465 billion years ago, war broke out over "ownership." The Giants did the heavy lifting, they argued. But how could they without the ingenuity of the humans, the humans would say. Had the dwarves not quarried the stone, there'd be no tower...
What should have been a symbol that they could accomplish anything if they worked together became a symbol of animosity. After a war with no clear winner, the groups went their separate ways, even so much as to develop separate languages.
Edit: It *stood* 3,180km tall at the time off the setting. It was destroyed when Theia crashed into the earth some 4.46 billion years ago.
If you're making something up off the top of your head right now to submit to this thread... Upvote me to anonymously advertise and "mood fam" the others who did the same.
The mountain of your upvotes might become the largest structure on this thread... and those who wander these forgotten halls when we are nought but memories on WayBack, will ponder with casual indifference as to who we all were...
Probably 'The Tower', if we're counting Dwarven buildings as 'man-made'.
It sits on a plateau with a carved staircase and has an octagonal base with sides of 200m long giving it an approximate area of 1.93×105m² at the base.
Its age is unknown and the name of the architect and the original design specifications have been lost to time, so the Dwarves are essentially just freestyling it for now. It's so big it may never be completed, for the building materials, labour costs, maintenance costs, logistics, trade routes may prove too expensive or unmanageable in time. It may even outlast Dwarven civilisation itself before it is finished, if it even can be.
It is the number one marvel of their people and it is a great honour to be nominated to live and work in the city that has sprung up around it to feed its steady growth.
Every clay brick is stamped with the name of its maker and date in cuneiform before firing, making it a civilisational tapestry of countless names and lives across unnumbered lineages. To be immortalised forever more in the most impressive architectural wonder in the world to ever be built is a privilege to be cherished until death.
Me upon reading the question: Oh cool, I've got a giant ziggurat!
Other redditors: I've been preparing myself for this question for ages, I know exactly how many meters tall it is and how it compares to other structures.
Katamari habitats. They destroyed the biome on their homeworld in an accident that released a nano phage into the wild. Now there are about 100 million left, mainly living offworld or in large O'Neill style habitats.
Out of necessity the Katamari developed far better tech to fabricate space habitats, and are in the process of revolutionising the industry. Katamari engineering firms do a lot of consulting work in this space now.
One of the largest structures built by humanity in my world is the planet Earth. After space trees tore the Earth into pieces, humanity took the planet and glued it together like fine China. It's true that many pieces of Earth were lost to the abyss, but much of the planet was rebuilt.
The Vürian Tunnel Networks. It is a connected tunnel system that spans under a whole continent that makes up 1/7th of the worlds total land mass. It was made by a precursor race which the current inhabitants - the Iwegi - occupy a small portion of it, and in their equivilant of modern day they are still trying to map out its full extent.
One that is not in ruins is the Baityian College of Edoic studies Super Conductor. It was designed by a revolution leader turned scholar Bertha the Blind who is a legend in her own right, a tower that stretches 200m high into a basement that stretches a whole kilometre under ground with a series of tubes firing particles at the speed of light, not too dissimilar to the hadron collider but with many more functions. The conductor led to the discovery of how edoic manipulation (or magic in laymans terms) can be used to manipulate ionising radiation without causing too much harm to the body.
I really like the idea of a bridge over an isthmus being the largest manmade structure in the world. Apparently even making them out of wood with Babylonian era tech there's not really any upper limit on how big such a bridge could be because you could essentially do what ants do and build a giant mound of sticks over the gap. That would give you a crazy arch that is basically a filled in semicircle, and so it is at the midpoint half the height of the span it crosses, and then at the edges is near vertical unless you built some offramps to reduce that which would increase its length yet further.
But yeah no upper limit on size.
I'm just trying to work out at what size it becomes cartoony. This isn't very scientific but I'm thinking .... the bosphorus is 700m and that looks doable. So I'm thinking a raging tidal isthmus between steep sheer 100m cliffs, a huge mound of a bridge that towers 500m high at its peak, and then long sweeping up and down ramps that make its total length well in excess of a kilometer. It's understructure is an absolute thicket of wood, maybe looking more like thatch than anything else, although each element of it is a full grown tree trunk log. But while the structure is thick, insanely thick, it does still stretch up to clear the straits by several hundred meters at the midpoint, allowing ships to pass.
And of course both the over and under sides of the bridge would inevitably become towns of sorts. Or rather, given the size, have multiple towns and villages scattered within them.
Not to mention at any given time parts of this bridge would be rotting and collapsing and being replaced, but not always in time to prevent local cave ins, with fresh timber.
A key character in my universe is an alien artificial intelligence whose physical structure occupies the region of, and is the cause of the significant gravitational anomaly known as, the Great Attractor.
The AI is known to humans as Xerris, who appears as a featureless, black, sphere with a diameter some several million lightyears across.
The structure is also “hyperspatially transient” and exists within multiple universes simultaneously.
Strictly "man"made would probably be the Stone Forest, an array of several hundred pillars that once held up a now-collapsed large concrete structure that used to cover an entire valley some few thousands of years ago. Nowadays it's mainly a digsite, considering it's the largest accessible site of ancient relics.
If something built by the God of Craftsmanship counts, then it's the Black Glass Tower, a massive building large enough to house a city's worth of people just in the bottom quarter of it. The deity in question lives in the penthouse with his family, while the other residents are mostly clergy, officials, and vendors - support staff to handle the constant influx of tourists and pilgrims.
Does the canal-system count? Back when the aliens were using the planet as a supply base, they had a railroad. While the rails were recycled, the ballast made it a good cart-road.
Unless it's something boring like a dam, my world's largest structure would probably be a folly. Native castle design wouldn't really get past the motte-and-bailey when mages are hell-bent on making warfare into a sportsmatch with casualties. Pretty much defensive fortresses would leap straight into fairy-tale castles.
**No Mans Land 2210** The Apollo-88 solar power plant. Built on what was once the farmland south of the Salton Sea, after advances in vertical hydroponic farms rendered them obsolete and wasteful, Apollo-88 is a 100-sq mi complex of heliostat reflectors built around dozens of receiver towers, as well as fields of classic photovoltaic solar panels. Everything about the place is made to generate electricity. Every building has panels on the roof and walls, the parking lots are shaded with solar panels. Even the floors that workers walk on is lined with piezoelectric materials so that they make electricity simply by walking about in the course of their duties.
The Salton Sea itself is used as a heat sink, helping to cool the liquids heated in the receiving towers in the process of generating steam to turn turbines. Apollo-88 generates over 20GW of electricity, rivalling the output of the few large-scale fusion plants still in operation. However, Apollo-88 has a much larger footprint than any fusion plant. The four large-scale plants in the Nevada-California two-state area would fit easily within Apollo-88's territory... with room for a dozen more.
Apollo-88 *should* be a juicy target in a post-apocalyptic world. But it's not. Electricity is seen as such a vital resource that any wannabe wasteland tyrant who wants to make Apollo-88 her throne and palace is met with fierce resistance, not only from the cities, but from allegiances of wasteland groups who normally wouldn't have anything to do with each other at best or are even hostile to one another at other times. These allegiances never last, dissolving once the plant is safe and reforming if it ever comes under threat again.
The stellar ring colony around the star "YR102-15700" (official name: [P.1F-43.YR102-PRA.157001.LAO-1]), commonly known as Praavia-Laotrea or Laotrea.
A colossal orbital ring, over 35 million kilometers long, that extends around the entire star. The ring is divided into four layers:
1. The first one, the “Sunny Side,” is covered with layers of gold, silver, and aluminum shields that have been polished to a reflectance rate of nearly 100%.
2. The second layer is a ring in the form of a tube with a counter-rotating, fast-moving magnetic fluid inside.
3. A network of superconductors extending from the first to the fourth layer, with long, shielded radiator “cables” is classified as the third layer.
4. Finally, the fourth layer is the actual colony itself.
This gigantic configuration allows the colony to dive deep into the star's corona and as close to the photosphere as possible. This, in turn, is done to better direct the large swarms of solar satellites, trigger controlled CMEs and solar flares, and intercept the magnetic and solar winds of Praavia-Laotrea.
The stellar ring colony serves as the main supplier of energy and matter to the star system. It extracts 1000 times more metals and minerals than any other celestial object or station/habitat within 1 ly of it COMBINED, while also providing enough plasma to keep the civilizations of Laotrea running for hundreds of millions, if not billions, of years.
Finally, it also serves as the main hub for repairing the SCH-Trustees and Sattelite Swarms, as well as transferring energy to interstellar stations and accelerating ships to other stars.
In one of my world, there is no human or humanoid, but only bugs, dragons and birds.
Bees are one of the species in this world, know for their skill in navigation and building. At the beggining of the world, the first Bees Queen traveled to a far-away plain to start the first Beehive. Because most of the bees is around 1 meter/ 3 feet long, the Beehive is HUGE, even after the creation of new beehive (all named after the distance and direction to the main Beehive).
The Beehive and its network of smaller beehive, coupled with the navigation skill of the bees, have made travel in the plains easier for bugs, until history separated the network between two ennemies bloc: the Good Community bloc and the Crow-Dragon bloc, where the Beehive is because they welcomed Egamel and the Spiders during their exile out of Good Community.
Was, it was destroyed a few milenia ago.
The Tower of Derual, kwown only as the Hollow Tower now, it was a gigantic construction of about 3km radius and 1km tall that serve as fortress and City to all the knowledge, guarde by the ancient god of Wisdom Derual. After a War where the Golden Emperor and the Dragon Empire tried to subdue everything, they seriusly damaged the tower, leading to it falling apart some centuries later.
New Alexandria. Created a few decades before the Great War or Godscourge. Humans had finally begun to rebuild society from ground up.
They gathered all the information about the old world possible, music, birthday videos, literature and even voicemails.
Alexandria was so large that a Draegkon could fly inside it for a month and still not hit the ends. It took up three continents of circumference.
A marvel of Havian engineering, coding, bookkeeping and resilience. It was so beautiful it made even Odin cry. He soon got usurped by one of his children. We never learnt who.
Thoth was their patron god and aided, so did the last remaining Norse dwarves who went extinct—someone had been silently executing them.
Humans were easily more advanced than they had been before they nuked themselves dead. The Library was supposed to be public domain, society was booming again and humans were finally changing for the better.
Athena burnt it down to nothing.
Some say that is when the war truly started. Sadly humans were set back to the 20th century in terms of progress. Radio waves were obsolete on Havia due to the high concentration of reality warping radiation and Gaia had grown so much that there were mountains larger than our "moon".
Humans stood no chance and forever mourned the death of Alexandria.
Now it's a myth.
The Condenser Wall probably. A 200 meter thick wall standing at 1200 meters of height containing enormous oil fired coils with coolant and fueled by five tandem wired nuclear tokamak engines tasked with cooling an area comparable sizewise to the City of Los Angeles or the Entire Bay area down to freezing point. The condensation also cools down a nearby pine forest and supplies it and agricultural areas with abundant water.
It’s the city of Zirkar. It’s an orc stronghold in the middle of the desert. It’s actually a giant three spired tower that is as tall as a mountain; it also has an extensive tunnel network underneath it. It is home to 100,000 orcs.
The black vault, a large repository of old tech made by the aleph roughly 4 to 5 solor systems in size, and due to the dangers of all this tech it is extremely well defended by autonomus systems despite being eons old at this point.
Not manmade but there is a structure named Cloches. It's described as a palace of bells born of a reef and dressed in the ocean's bluest shell, where a clock delivers the message of the silver sun down to those below. It serves as a dungeon throughout an entire arc in my novel series.
It's a labyrinth of 12 gardens, each with the goal of forcing those in pursuit of its apex to give up and accept their fate. That fate being an inevitable death when Cloches' clock counts down from midnight to back again.
It's a lot to get into, but my world, and series at this point, centers around my protagonist's journey through the new world after she brings about the end times in the previous one. She has no recollection of her past life, but when she left it, she left behind six brothers, of sorts, who also awaken to this modern age. Only their minds have been twisted and their forms followed, resulting in each manifesting as a different "final boss," or whatever you want to call them---again, a lot to get into.
Cloches is the second youngest brother, reborn as the palace, his mind set on delivering a "cure-all to life" as he refers to it. An end to struggle. Death. Swift and unavoidable.
Rail Flower.
It would be ridiculous to call it a rail yard when it spans farther than Pangea.
In addition to that the trains themselves are larger than that of the Burj Khalifa itself at times.
On a planet the size of the current observable universe, these trains travel at 99% the speed of light.
Yes, sure, you have FTL as an option, but that requires you to get OUT of the atmosphere first, and do you have the money for a ticket to the space elevators? didn't think so.
The Red Tower.
Home to the Red Wizards of Sunhold, the Red Tower was a structure built by the wizards who study the dark magics shunned by the majority of Sylvarra and Ebonreach, and is used to maintain the dark magic they practice. Without proper skill, or knowledge, casting spells that are considered “dark magic” can become uncontrollable and unmaintainable which could result in many different outcomes ranging from the death of one individual, to hundreds, to crushing a castle or even sinking an entire landmass. The wizards built the tower and created pocket dimensions they access using portals which allow them to practice these magics in order to study how to defeat them without the risk of someone losing their life.
The generally largest structure is the Prescott Basin Mine, a mine dedicated to supplying most of the world’s rare elements, and Thiaenium, the element for magic.
It goes around 47 miles down into Pramaria’s mantle, where most thiaenium is located.
The largest “structure” structure, is 119 Lucio Street, known more commonly as “Lucio Tower”. It is the largest skyscraper in the world, and is atone to the WTC in Manhattan. It hosts galactic meetings, is a huge center for trade and commerce, and hosts many other businesses and apartments.
Probably "The Black Keep".
It's a large asteroid base consisting of several asteroids. It's purpose is to airstrike strategic locations as well as deploy specialized troops
The Playground. Playground was builded by gnomes as a bunker but Kupid decided to turn their bunker into a heaven. On the outside, Playground is a massive building that is literally "The Square". It is 200 kilometer wide on every side and 15 kilometer tall. But on the inside, its infinite. Thanks to the Kupids god powers
I would have to say my ring world (the Shikar Ring). It stretches all the way around the local star. Most of it is uninhabitable though. It's left over from the old human empire before they almost got whipped out.
Now the current empire (the Shikar Imperium) is trying it's best to scrape together the remnants of what humanity once had.
The so called Ancestral Empire was really into building massive constructs. So now the galaxy is littered with the husks of these wonders.
The all speaking tower of king Morydd.
A tower made by his hand allowing him to preach to every living soul on earth. It extends over the atmosphere on a base of rock that spreads through the land. At the bottom are bridges that connect the tower to every continent.
The Aether Apparatus, found deep within a Major Dwarven Ruin, it's a massive pillar like structure, while the actual size remains unknown (more then two miles long and half mile wide), it generates a pulse of uncontained Aether Energy every so often to the top. It's believed to been a power source or a weapon for the Dwarfs before they vanished.
Aether Energy is highly dangerous as it causes various effects to life so every time it pulses anyone within the large room with it experiences intense pain, magical feedback, major burns along your body and if you happen to be standing close enough you'll get vaporized.
Alien facility under the ices and landmass of Antarctica, covering almost entirety of the continent with it's rooms, halls and tunnels.
It is partially in ruins and its exact function is unknown, aside of clear connection to the Days of Oblivion, it appeared during.
Big. Fucking. Bridge.
Made to cover the gap between two close mountain peaks separated by a massive cavern. An order from a dwarven king, with a lot of Orc contractors as well.
Amazing sight to behold, absurdly large. And built to withstand anything!
(Halfway through construction, things went wrong and resulted in mass death of the construction workers, after that happened, they just continued building it. Many More people died for various reasons. but it didn’t collapse this time)
Haven't revealed the hole story yet (not sure about the numbers too) but there was royal cities ruled by certain kings who desire (or manipulated) to reach to the sky to meet with gods. With this purpose they forced their servants to levitate the land around their castle to build a tower under. Promised their servant to when they reach to gods they will ask them there too. But so many years past servants keep building these massive pillars and no one knows what happened to these people who stuck on the top of the towers. (except me eheh)
The Dead Wall.
So in the east there are three cites (roughly analogous to Prague, Vienna, and Budapest). Prague is ruled by a Lich, Budapest is ruled by a Vampire Lord, and Vienna *literally* the ghost town where they fought their war against each other. Well, there's another city (roughly analogous to Rome) that built a 200+ milt long wall on their eastern frontier to monitor the Dead Lands and to ensure that no dead or undead creatures make their way toward civilization.
The Vision Tower, a tower soooo tall that if you went to the top of it you could see the whole world (My world is flat). The tower was made to spy on other nations by the Empire of the Center. The tower is also used as a giant net to catch flying lobsters and birds that the people below eat.
Probably the city of shelves. It's a city home to the largest shopping center in the world. Drones made by long since vanished inventor collect junk that rains down outside the city and put it up for sale within the city. Nobody really knows how big the city is since it's larger on the inside than out, and the shelves go on seemingly forever. Edit: The reason for its out of control size largely comes down to the fact the drones have been engaged with the last command from their creator for so long that things have gone haywire. Drones sometimes act irrationally, and there's entire segments that are unmaintained and unlit, not even being recognized by the drones as part of the structure.
Thats fucking badass dude HOLY SHIT
Thanks! The initial idea of a large space made of seemingly endless shelves of items came from a dream I had. It slotted in almost perfectly with the existing junk heap area I already had in the world at the time. It's since ballooned into one of, if not the most important location in the world I've made just due to it's implications
it has so many uses narratively too you could use it to give a character a new tool, sent them there for a hunt maybe, it also has such a ambience that is very unique i love it, maybe some drones are malfuncitoning and you would have to fight them?
Scp-3008
so backrooms basically
Except, instead of being a place you can no clip into it's a location people visit to search for stuff. My whole world draws from surreal media like Yume Nikki and Antichamber.
Love antichamber fuck yeah
Same. Originally the world was just a giant Edifice with Antichamber like gameplay but expanded to be a world with physics and space that doesn't make sense. Spaces being bigger on the inside than outside is not limited to just the city, it's just how things are for the people.
Madman made a non anomalous infinite ikea. Very cool
Allot of my world could be classified as anomalous. The junk plains and city of shelves is more fleshed out than other areas at the moment though. Since you can find just about anything there people come from long distances to shop around.
Reminds me of a manga called Blame
This reminds me very much of the world in "BLAME!", it's a great set of books I find.
I liked the BLAME manga. I read it some time after the location was added. I'm a big fan of surreal and dream like media.
A short stay in hell has similar concept. It makes the reader feel so insignificant and out of breath. I really like your idea too. (◍•ᴗ•◍) very intriguing!
Coincidentally I did just add that book to my to read backlog. I look forward to reading it!
How long time did it take to build this city?
I don't really have a definitive timeline for events. If I had to guess, hundreds of years of expansion, renovation, upkeep, etc. The creator of the drones made them with the idea that to accomplish their task of collecting and selling items they would learn to innovate and adapt over time, so I'd imagine things got easier and easier over time as their tech expanded and more drones were made.
That is super awesome. Reminds me a bit of BLAME.
SCP 3008?
I had more of a antique/thrift store vibe intended overall. Very warm lighting, with tall shelves full of random junk. In the unkept parts of the city, items sometimes move on their own, and some shelves extend farther inwards than they should.
The Ananse have a partially completed Dyson Sphere around their host star. Ananse names don't translate well into human language so most of humanity just call it "The Sphere". It's primary intention is to provide energy for science project but also serves as a nuke dampener and laser array, essentially vaporizing anything in the solar system the Ananse don't want there. Unsurprisingly, no one has even tried to attack their home world.
The Enlightenment Project. A massive ai hyper computer constructed into what was once the Himalayas. Built to save humanity from a total climate catastrophe, it was effectively an artificial god that took requests like some combination of ChatGPT and the Monkeys Paw. It was instructed to save earth from apocalypse, and it did so by removing all traces of humanity actively harming the planet. Just deleted. However, due to either a deliberate choice, a coding error or hardware failure, it forgot all but one detail about humanity. Humans had no exoskeleton, and were not insects arachnids or arthropods. This resulted in every species other than the 3 groups previously mentioned being deleted as well.
Remember kids: Never cheap out on QA when you build an AI god :D
The Monoliths. Known more officially as **Large-Planet Deep-Cities**, Monoliths are super-structures built nearly 500km into the planet's core to harvest raw materials deep below the surface of the planet and housing the billions of people within them. These same cities also climb nearly 1500 meters tall, looking out over the vast horizon for miles around with towering skyscrapers. The entire structure is suspended by super large and powerful magnets over the planet's outer core. The reason for their existence was because of a near-apocalyptic event that had occurred with the eruption of the last super volcano on Arius. Blowing its top, this thousand mile diameter super volcano exploded in the mid-3rd millennia, spitting trillions of tons of ash into the atmosphere and wiping out vast amounts of life and food resources. Humans retreated to cities and what followed was a necessity to grow and survive in this now cold and ashen filled world. In time, these cities expanded downward to make room for more housing, industrial zones, and vertical agriculture farms to support the population. In the year 4323 P.E, 99% of the world's population exists within these cities. Crime is high, education is low, and people in all classes are just barely surviving.
The Stratower is the largest skyscraper in the known universe. There are colony starships larger, but nothing terrestrial. The Stratower is the size of a city, and its pinnacle is a spaceport that protrudes above the stratosphere.
My brain immediately went, "Wait, that sounds like it was word-for-word ripped from my favorite sci-fi books." And then I read your username. I absolutely love the Torth series! The depth of your world building + the sheer unique nature of your characters makes the books impossible to put down. I've been on a sci-fi binge for six months, and Majority is my top favorite out of over a dozen books. The way each book mixes mystery, scifi, fantasy, action, and dystopia fills my soul, and I'm genuinely sad I binged them all so fast. I have a timer on my desktop counting down until Megacosmic Rift releases!! Thank you for some of the best books I've read, ever.
Thank you so much! This comment made my day a lot better.
How long does it take to go up and down the tower? Is there a super fast elevator system or some other kind of transportation?
There is a superfast bank of elevators in the center of the tower. It still takes several minutes to get from ground floor to pinnacle.
The Mail Tower, a roughly 100 metre tall structure that acts as a central hub for the postmasters guild. There is much dispute over whether the Mail Tower is a single building or not. This is because there are several Mail Towers, yet only one of each of the rooms inside them. For example, if someone in Kuvshinka and someone in Dragoskala were to go into their local Mail Towers at the same time, they would meet up on the first floor lobby, despite entering from cities several miles apart. This is yet another reason why the Postmasters so thoroughly control the mail, as the Mail tower allows them to remain centralised while still dispersing their influence as far as possible. However the Mail Towers are not without flaw, as they only exist in the four population centres and cannot effectively deliver mail to areas distant from these three cities. It is believed by many that this flaw is why the colony of Slavaduyn perished.
Ooh, it's so cool that they're all the same tower inside!
The Great Mount is a mountain fortress that was raised by the gods (who are humans masquerading as gods so it *is* man-made technically) in the wake of the First City’s destruction at the hands of the betrayer god. It served as their stronghold in the mythic Dread War against this betrayer. It looks *almost* like a mountain, only it’s too steep, and *far* too tall. So tall, in fact, that its peak pierces the earth’s atmosphere, and the palace of the gods is immersed in the perpetual gloom of outer space. The supposed saviors of mankind live in a place devoid of both life and light... The Great Mount is surrounded by the Chasm, a crevasse that surrounds the fortress like a massive moat. A half mile across and so deep that no one can see the bottom. Some believe that the Chasm wasn’t made to serve as a moat to protect the gods, but that it was carved out by the Betrayer himself. That he had sundered the earth to set free the million million demons of hell to fight for him against his divine siblings in the Dread War. Whatever the case, no man who's attempted to cross the Chasm has ever returned from the bottom, so who’s to say hell itself doesnt lie at the bottom
Naryil's Capillaries are man-made by technicality, being a tunnel network dug by a biomechanical drill. Its original mission was to connect two of Ardeia's undercities together as a vanity project, but was left unattended by humanity for millennia and has since looped over itself uncountable times. It stretches below a 500-km length of the Hunchback Mountains in the present day, with local traditions honoring it as the road to the underworld. Doya-taj is a more contemporary 200-meter tower built by the Lajean Empire in their efforts to expand their wyvern riders' effective fighting range. Overlooking the vast Nawasu Steppes, Doya-taj is the one and only spot along the frontier that wyverns can comfortably roost and recuperate between sorties.
The World Trees, gigantic space elevators connecting Duna to the Ring. The biggest one, Yggdrasil, is only slightly bigger than Olympus Mons in diameter and a few million kilometers in length. Long enough to extend past the orbit of the moons.
I haven't solidified everything, but it's probably either a palace or an armoured airship. Both kind of explain themselves. The airship probably has more of a *need* to be bigger due to requiring the buoyancy, helped by a thicker atmosphere. The largest ones are built by the southern empire and have various roles from transport of troops, supplies and vehicles to extending clear radio signal ranges to providing aerial power projection (including artillery fire and sometimes launching planes). Lapis_Wolf
The Great Wall of Gryll (I know, unoriginal name) was built by the Gryll Empire for defensive purposes. Primarily it's meant to keep the Wildings out, with mixed success. (Wildings are eight-foot-tall, horned, furry walls of muscle who are exceptional at climbing.) It stretches a couple of thousand miles along the western border.
Largest “man”-made structure would be the Golden Goose Casino, simply because it’s so big half of it has to be shunted into SEVERAL separate pocket dimensions to fit everything….it’s basically it’s own country with how much it has
Depending on the context, but I'll go for tallest since the largest structure in my world is either a warehouse or some giant dam no one has heard of before For some context, within Ahikto, starting in the mid 2000s, there was a large "skyscraper boom" which lead to the construction of nearly 100 buildings taller than 300 meters across the world. Most of these were located in the newly established capital city of Temugin. The tallest building is, funny enough, still under construction but has long surpassed the tallest building in height. **Kishinato Tower** is 1,347 meters tall. A weirdly specific albeit consistent number. This building has been under construction since late 2017, and will overtake Daxiang Tower at 1,140 meters tall. Kishinato Tower is the third to last building to be completed within the Kishinato City World Trade Center, with WTC 11 and WTC 13 still in the planning stages as there are buildings on the site that would need to be demolished. Kishinato Tower also, funny enough, is going to be completed soon. Its expected to finish construction in Late July this year and open the public in early September. (Fandom Link since I haven't migrated this page over to the miraheze wiki yet) [https://ahikto.fandom.com/wiki/List\_of\_Buildings\_by\_Height](https://ahikto.fandom.com/wiki/List_of_Buildings_by_Height)
Define "manmade". If you mean made by humanity, they're the Passes built by Atreisdeans. Such Passes are 20 megameters across made to connect two ends of an Einstein-Rosen Bridge (or in layman's term, wormholes) together and stabilize them enough for large fleets to move through. Spaceships move in large formation so they won't accidentally crash on each other because gravity works funny inside the tunnel. In extreme case, they can yeet **entire rocky planets** through the Passes. Largest artificial structures belong to L'Aurelles, a race of space jellyfish-men transhumans. They build enormous biomechanical Dyson spheres called Vor'toms around stars to absorb photon, which is their primary "food". Vor'toms can control gravity of their own, affect a star's spinning speed, and can **drag them along**. There was a case a L'Aurelle colony departed and they took their Vor'tom, with a Sun-level star inside, with them. There's a reason why Atreisdeans, with their system-erasing time-travelling *common* weapons, don't want to anger L'Aurelles.
The City of Kelis is the largest manmade structure. It is carved out of the bottom of what was once the largest mountain in the world. It serves as the hub for the largest religion in the world, around half the population of the city works directly for the religion, and the rest work in roles which support it.
Scattered across the main continents of Dorowhen are enormous towers (about 450 feet tall) that can be best described as structures of cubism architecture made out of crystal circuit boards. These are the Geospires, a remnant experiment left from the days of the Primarch Empire who used these continents to test out potential terraforming technologies. Each of them creates and actively maintains a constant environment in about a 200 mile radius, and are the cause of the strange climates found only in this region of the world. There are currently three known Geospires in the world. Cryospire, which creates a frozen tundra quote close to the equator; Dessicant Spire, which created the Kelsan desert (which has been slowly spreading and threatening to desertify the rest of the continent); and Verdant Spire, which created the jungles of Istulra where the Beast Folk (another large scale experiment left behind by the Primarchs to give animals sentience) make their home.
Fantasy: The Catacombs of Nahm, a vast underground complex that houses the remains of desert God-Kings long past, as well as their relics and other valuables. The catacombs span the majority of the western desert. Sci-fi: The Rift Engine, a massive machine using advanced extradimensional technologies that is being constructed in the cyborg-claimed desert. Its true purpose is unknown to the world at large, but it has been theorized by one rogue cyborg who has absorbed a piece of the material that it may be an attempt at either immortality or a wormhole generator.
Du mama?
The larges artificial structure is the setting. It's a Birch World. It has more living space than whole galaxies. If you traveled around the equator at 10,000 miles a day, you would take a paltry 6 million years to complete an orbit. Also, it's so large and heavy, escape velocity is basically 90% of the speed of light... so no one has left since long before it was finished. It's also old. It was finished so long ago that stars were still burning. Now even the youngest of red dwarf stars has burned out leaving the universe outside of the Birch World dark and cold. But inside, life thrives. Each level of the structure plays host to one of the races that helped in it's creation, though now no one is sure how many levels there are.
The largest known structures in my sci fi world are these mega structures called “Galactic Forges”. They were used by the Ancient Ones hundreds of thousands of years ago to build new stars and planets (even entire solar systems if they wanted) to how these demigods wanted. They were spherical and its width was 2.8 billion miles which is the orbit of Neptune as a comparison. From what archaeologist decoded of the ancient one’s complicated language 12 were destroyed with 1 remaining uncounted for so it could still be out there.
The city of Aurora, humanity's first great step into the stars. It's this enormous interconnected city that contains examples of every architectural style in history. The old city, now the undercity serves as the foundation for new construction and many of the buildings there have been completely filled with concrete for this purpose, the poor down there will carve pueblos directly into these concretes facades. Everything is so densely packed and every space is used. High above, in the peaks of the city the buildings are sealed because they're so high that air needs to be supplied. Aurora is 12 citied stacked on top of each other, each more advanced and lavish than the last. A continuous construction of skyscrapers and towers for more than 1400 years.
There is a series of underground bunkers, laboratories, and military facilities that are connected by high-speed railway tunnels below the United States. It is known as the Mycelium Network. It started as separate facilities that were constructed in the 1940's, 1950's, and 1960's. In the 1970's, they began construction of tunnels to connect them and the high-speed railway system officially began operation in 1986. New tunnels and new connections were being built throughout the years right up until the Nuclear War of 2029. The Network got so large that is was possible to go from Washington, D.C. all the way to Nevada and California completely underground. The purpose of the network was so that the U.S. government and military could continue their activities in the event of a disaster. It also served as a convenient transportation system to transfer clandestine items from one facility to another without drawing significant amounts of public attention.
Depends on how you define 'large' - if it's something like sheer coverage, that would be the Lycadian Food Pyramid...I'm pretty sure there's no existing structure on Earth whose foundation covers half a mile in every direction. As for its purpose, as its name suggests, it's a giant arcology-esque greenhouse.
There's a massive wall of some strange alien metal encircling the entire northern sea. It extends from the sea floor to just below the surface of the water, and it glows with mysterious runes in no known language. Massive electrical storms and strange auroras dance in the sky above it, and St. Elmo's Fire flickers across the masts of ships which venture too close. No expedition has ever managed to cross this wall and see what lies beyond at the planet's north pole, but rumor has it that the wall guards an ancient, technologically advanced civilization. The land beyond the wall crops up a lot in fiction - it's kind of like this world's El Dorado or Atlantis. In truth, beyond the wall is just a barren, icy sea. The real ancient civilization is within the wall itself. Unbeknownst to the people of this world, the wall is actually a huge, ring-shaped spacecraft which ancient humans used to travel to and colonize this planet.
LightTower. Is 50× times thiker than texas and 1000× taller than the empire state building.
Blackhole Dysonsphere. It also counts as the biggest manmade bomb in the setting.
If you stretch the definition of 'structure' a bit, then the grand archipelago is the largest. It's a collection of naturally occuring floating islands held together with man-made bridges and chains.
March of Empires has Galactic Rings. Enormous structures surrounding the boundaries of the galaxies under human occupation. These are located on the Galactic plane along the entire boundaries of the galaxy. They have swarms of pure energy-made USVs, also called Unmanned Space Vehicles (E-38 and E-39 are the units in Operation on the Rings). These serve a multi-purpose role: Fortresses to launch defensive maneuvers from, and the use of the drones to map and locate potential sources of energy. Intergalactic trade also happens often through this sector. It is Enormous, lightyears long. Their defensive systems are some of the best, including Intergalactic Sterilization Sniper Cannons, Stellar Rays, Statofortresses, Stellar Phantom Bombers, Bullet-Class Cruisers, Hyperspace jammers, Universal Communication Jammers, Imperial-Class Destroyers, and Cybertronian units. Entire armies can be launched from it: made out of Stellarium, which stays at high temperatures, Galactic Rings are flexible and can open doors almost everywhere. Everyone wears heat suits and consumes coolant drugs to keep themselves from burning alive. The power required to destroy a Galactic Ring is equal to the power required to destroy a medium-sized galaxy... so a civilization needs to be Type-3 with similar military power to achieve such a feat.
Arguably, the setting itself. So many things need to go *right* for the Skyring to exist that natural generation seems unlikely. Its not *impossible*, mind you, but is almost certainly unique in the galaxy, if not the universe. If the star is too big or active, the gas ring won't form with hospitable pressure. If the gas giant lacks oxygen, that gas won't be present in the gas ring. If the gas giant was any closer or further to the star, the sky ring would simply fail to develop in a stable configuration. Combine that with Builder "Temples" that seem to do... something in regards to the Skyring, along with enough advanced technology in them to suggest that stellar body manipulation wasn't necessarily out of their league, and there's a good argument to be made that the Skyring might be some alien experiment, art installation, or the like.
The Tower of Babel still remains the tallest building ever built, being approximately half a mile taller than the Burj Khalifa. What happens when humanity once again is able to reach those heights? ... ...
In the future, a giant space station was built that was only a little but larger than the moon. Like the Death Star in Star Wars. It was built as a way to transport to other planets in the solar system for terraforming. My world's whole gimmick is that humanity had to restart mostly from scratch after most of civilization left for other solar systems. There was a secret society that was left with all the technology humanity had before they left, being the most advanced civilization. After the man made moon was not in use anymore, the secret society planned on using it as a beacon to signal the rest of the humans in the sky to come to earth. They would send a giant laser up in the sky, hitting the satellite, then it would refract and spread the laser throughout space so then they can hope they would come and save them.
Hell's gate. built hundreds of years before the Storm of Light, the 50 mile high volcano fortress stands as testament to the supreme power of the early demonic lords, its solitary tower sits on its obsidian slopes, now the only known part of a once feared fortress, it is one of the worlds largest castles In it's own right. the entire volcano is at present being mined by elves, as the magically mutated evil gold ( or De Nyryngyld if we're speaking modern Tymori) can be used to create wmds.
The Pendula. They were constructed before the Schism, as a way to evacuate large population groups at once. Essentially they were massive elevators, bridging several continental land masses with Planets. Of the three planned, only two were completed: First Elympos, which was connected to Earth, and the Broken Watcher, which reached to Mars. It is largely unknown where the third Pendulum, called the Pariah, was meant to send wayward refugees. First Elympos was successfully activated, with evacuees documented in the tens of millions. The Broken Watcher, on the other hand, was met with failure. The tower’s mechanisms suffered crippling faults when Daluvimenrais burst through the rift between the world and his prison in Trolos, which invoked the Vestige of Floods and triggered the Schism, thrusting the Planets from the sky and into another dimension. Any lives that reached the surface of Mars are believed to have perished in the impact. All three Pendula stand as looming ruins casting their long shadows over the civilized world, people having long forgotten their purpose.
Currently it is the Grand City in the Azron Valley in the nation of Kyzanta, which is essentially just this bigass pyramid. Unfortunately... this structure was not made by man - or even any currently living races for that matter, and gives more questions than answers. All I can say is it's currently used as a tourist trap in recent times.
The current largest ~~man~~Ketuvyx-made structure is the Allocator, which is a facility on ~~Europa~~ the ice moon of planet 5. Its purpose is to receive starlight from a distant, abnormally bright star via breachgate satellites and, using a clever setup of lenses and more breachgates, condense the light into beams for whatever use is necessary. That could be using some to generate usable power, or it could be focusing raw starlight through other breachgates for use as weapons. It's currently the size of a small city but is planned to be expanded until it covers the surface of the moon (along with more collection satellites launched). Looking at the broader setting, a ecumenopolis from one of the older species may count. In the far future of the setting that's ill-defined I'm entertaining the idea of the Ketuvyx Ascendancy constructing a Birch World, and maybe even beyond eventually.
In the world of Solaris. The Floating City of Titan: Anchorport A massive city built from hundreds upon hundreds of ships. Thar have been Frankensteined together. Explorers, adventurers, researchers, pirates, just about anyone really, would make their way to the archipelago controlled by the Titan Empire hoping to strike it rich in the under water labyrinth known to be one of the Graveyards of the Gods. Areas of Solaris where the gods fell and their corpses warped the landscape, civilations fell and monsters began to lurk. Treasures and resources ripe for the taking, and a lost history waiting to be unfolded. Over 1000 years of ships have stayed behind as thousands lay there below in the underwater grave, though a curious clan of shipwrights always maintained the ships, hoping the explorers would return. It became so packed that the ships began to be built together from the confusion of maintainence. Those few that did return, usually, empty-handed, would find their ship melded with another. With no way to return most would stay. And thus Anchorport was created.
Elas itself is a massive artificial world currently shaped like a bowl with six arms stretching towards the sun, though I'm considering other options atm. It was built by technologically/magically advanced race from another reality who act as guides and protectors of the mortals. Inside Elas the largest structure is the Forgespire. A tower standing a half mile above the desert sands, and extending just as far beneath the sands. At ground level then Spire is a hexagon covering approximately half a square mile. The Spire is home to the bulk of the race of clockwork constructs known as Forgeborn.
one person had made a maze, 100 by 100 km. it is called the splitted maze, because in the middle is an open place that is splitted into 2 places where two groups of people lived. it is so big because the builder likes to be famous and must have a place to put some dangerous monsters in. the monsters can't solve the maze.
The Castle-Complex of Gurenthan. Larger than some countries, has survived being attacked by the god of death himself at full power. Is also the oldest because it just survives apocalypses .let me know if you want to know more
Old Engress is an abandoned underground city that traces its origins back to a gold rush in a region filled with dangerous fauna. A massive series of mysterious underground caverns were discovered in an untamed land, filled with valuable ores, rare gemstones, crystals, you name it. When those caverns were discovered, the continent was under the thumb of a great emperor who dedicated vast resources to tapping its riches, kicking off a golden age. Great beasts and monsters inhabited both the caverns below and the wilds above. Townsfolk often holed up in the mineshafts. Bunkers were built for emergencies, and those eventually became permanent residences. The whole town moved underground and as the massive caverns were mined out with no end in sight, the city expanded beyond reckoning. It was resplendent and exceedingly prosperous, with roads lined with gold and jewels. This continued for about a thousand years, the caverns seemingly unending. Old Engress became so large and porous from mining that it was largely indefensible. In the meantime, the surface had been long tamed for living and agriculture. Old Engress was hastily abandoned for the surface following a collapse that overwhelmed its defences against the deep. Engress sits above the abandoned city, and its mining operations have turned to scavenging the abandoned riches below. Old Engress teems with dangers and the caverns below it are largely considered lost to the creatures of the deep.
The Arks. Five were created to save the world's population from imminent cataclysm. Only two returned to the now shattered planet. One was lost to gods know where, one was besieged by aberrations in space and is now a danger zone where no one dares travel, and one fell in the ocean.
(All characters are the work of fiction here and not to be associated with real persons!) The Capital of the Galactic Commonwealth, and its Royal palace. When the Brits colonized the LaCaille System in 1971, her Majesty the Queen and the British Nobles demanded a new Palace for the Royal Family on the new capital planet of Ashworth-336. The construction began in 1972 and was nearly finished when the news of the war on Earth interupted the whole project. The evacuation of her Majesty and the royal family was an utter faliure and almost every family member had died after their shuttle has been hit by a raiding party. Only the Teenager Princess Anna II had survived, and was mortally wounded. When the shuttle was found by the United Colonial Space Forces, the princess had been aided and escorted to Ashworth where she became the new Queen of the Commonwealth, and finished the royal palace after a year and a half mourning her family. She demanded the palace to be bigger than ever… to be the biggest building mankind has ever seen. To be the shining Jewel of the new Empire, a tribute her fallen family, to the Queen. With that, the palace has been finished by 1986, a neo-gothic, multiple hundred story building decorated with more gold than the entire gold reserves of old earth ever had. This is where her Majesty Anna II. and her government rules over the Galactic Commonwealth.
Space elevator cities. The elevator lifts into the sky. Then, the oqning corporation builds multi-leveled cities around it for maximum profit.
There are a couple of different answers. I have a list of natural and constructed wonders of the world and a few of the constructed items stand out. The longest structure is the Imperial Road in Faras, a large central road that is heavily barricaded by ramparts made of obsidian. Stretches the entire length of the kingdom. In the distant past a king now known only as Lofelk the Strange basically ended his rule through the madness of this project. The unholy amount of labor required combined with a lot of people not being compensated at the end caused an uprising that dethroned him. No one really knows (I haven't come up with yet) why he commissioned it and why he wanted it to stretch the entire length of the kingdom (even past the last major city in the far north to reach the barren coast). The most massive is a large bridge that spans a large sea that connects two twin capitals, Egrin Lilith and Drus-Tirith, as they represent two kingdoms that have combined. An elven kingdom adopts a population of halflings that had to abandon their original home. They give them some land and help them build a nice city. The bridge is supposed to be a physical representation of the connection between the two peoples. And it's big because the sea is big, lol. If this would count to you, the most voluminous is probably the caverns inside Forak-Khagal, the capital of the main dwarven kingdom. A large fissure in the ground in polar ice is populated by dwarves who have many structures built into the walls of the fissure that lead to a large and elaborate underground city. And it's big because dwarves are cool like that.
Well, there's a lot. Black holes a lightyear wide, trains that cross between galaxies and even galaxy clusters, and of course the giant resource hoard they build after all the stars die out, made from all the galaxies they could bring back home at under the speed of light, so it's basically the size of a galaxy but way more dense and has tons of connections between the various nodes. Yeah, my world engages I megastructure engineering constantly, to the point where dyson spheres are just a given and are viewed as like setting up a tent for camping. In fact even back when they had only colonizedthe milky way they had more dyson swarms than we have people (400 billion to be exact) and now they have 120 billion galaxies just like that, though only a fraction of that was incorporated into the primary hoard.
Bastion Station was built by the Architects at least 72,000 years ago in the Astra Galexy. StarCom found it in 2003 along with the other structures. While the Architects build larger things like Dyson Spheres and Ring Worlds, the station was the largest still standing after the Relic Wars. Most archaeologist believe the Architects built the station just because they could as some from of challenge. So far only 20% the station is inhabited due to a mix of archaeological excavations, critical repairs, and a simple lack of people to inhabit it.
The Library of ancient runes, relics, and scrolls The library has millions of scrolls its seems to reach the gods because it almost reaches the clouds. It was made with elven wood, Dwarven nails, titans strength, and humans math. It's used by God's and goddesses alike, to learn ancient magic this is where you will want to go. In my story I made the main protagonist named Mizuho had gone here and stole the bow & arrow of the Nature God. Many relics are held here, I will some of list them off • the staff of judgment • the daggers of lust • the sword of hatred • the axe of pride Each made bye God's and blessed by the creator.
Out of all the megastructures humanity has built, Dyson spheres, massive habitats and gateways, entire planets converted to warships, massive vessels that serves as a city and a spacecraft at the same time as a mobile Spacedock, all pales in comparison to the Avalon class of ring worlds. A massive loop at over 10% of an AU Wide, each station is indestructible, and is home to trillions. Equipped with enormous defences and many stations, along with a massive shielding system, only three of these titanic ring worlds have been built so far, with no plans to build any additional ones
The Front Line. So when the apocalypse happened, it caught the precursors with their pants down in the middle of whatever they were doing. In this case, they appear to have been fighting a massive war. It's unclear what this war was about or even who was doing the fighting, but its remains are still there seven hundred years later. The Front Line is two lines of miles-deep fortification lines facing each other across a no-man's-land. Behind these lines are miles upon miles of artillery positions, command posts, and logistics depots. Mountains of rusted spent artillery cases tower into the sky. The line is so long that it bisects the entire continent. While not necessarily the largest structure, the Front Line is certainly one of the longest in the Underscape. While the war is long over, the Front Line is still very dangerous. The automated defenses still appear to be mostly online, and mechanical monstrosities still roam the deserted trenches and bunkers. Landmines, unexploded ordinances, and other traps litter the scarred landscape. Traces of poison gas still infect the air. However, all of that pales in comparison to the true terror of the Front Line: Netwire, one of the worst surviving creations of the precursors. Netwire is mechanical razor wire that can move and appears to be somewhat sentient. Netwire hunts those who wander into its territory like a predator, striking quickly from underground and dragging its poor victims into the mud to do God knows what with them. Since Netwire cannot eat, it is theorized that it hunts for pleasure. The infernal wire has even been known to use the bodies of the dead like puppets in order to lure in new prey. The Front Line is absolutely infested with Netwire, and that is reason enough to not go anywhere near the place. Those who have seen the Front Line are often left with profound sadness. What sort of monstrous hatred could have inspired such horrific weapons? Whoever the precursors were, perhaps it is best that parts of them remain buried.
Technically, it's not man-made since the Ancients built it, but the Observatory is the largest single structure ever built. Its foundation is on some backwater elven farming world, but it extends out into the void between worlds. Because it isn't in conventional space, its height is technically infinite while still being finite. It is not recommended to look up at it from the ground. The sight tends to induce extreme vertigo and an acute sense of insignificance. It's purpose is to take advantage of the observers' paradox on the macro scale in order to tie the worlds together and keep their clocks in sync. Without it, trade between worlds would be impossible since a traveler may arrive at their destination hundreds of years before or after they left. The Observer is magically tied to its massive sensory apparatus and can use the multitude of sensors to observe anything under its aegis.
I think that would be the Truesilver Tower. Not quite sure though, I would have to go and measure. The most important building in any given elven settlement is always a tower - for cultural reasons. And the really big or important towns and cities are built \*as\* (or converted to) towers and always expanded by building another layer upwards. The White Tower, the center of elvenkind, was such a city. After a cataclysmic war at the end of the last eon, the center of elven culture and nexus of magical prowess on the continent had been razed. As a sign of gratitude and eternal friendship, the dwarves of Dragon's Maw shifted their still running war time production from arms and armour to building materials and went west, to rebuild the lost elven tower. With their mines and workshops working at peak capacity the dwarves were able to invest vast quantities of mithril into the construction project. The result was a tower double the size of the original which was seen as basically indestructible and renamed to fit its new coruscating appearance. You'll probably never lose your way when you try and visit the elves in their tower. It rises high above the trees of the forest and seems to be tickling the clouds.
The Saffron Lifewall is an enormous dam with a huge complex of integrated mills. It got its name because laboring conscripts engaged in work stoppages, driving the project behind schedule. As punishment, the Emperor decreed the locals would cover the complex in a costly color of paint, at their own expense. The region seemed headed for severe economic hardship, but within a generation it instead became a thriving center of industry. Now locals keep that eyecatching paint in good condition as a beacon to traders and travelers keen to part with coin at businesses around the Saffron Lifewall.
The largest human-made one was the Global Climate Control Grid, a massive orbital structure connected to the planet by several space elevators that consists of several rings, hundreds of stations, and untold numbers if smaller satellites to precisely control the earth's climate and act as a sort of "hub" for Interplanetary travel. Sadly it didn't last long, collapsing to the surface after only a century due to unknown reasons. If you count other species well, the city Planet of Ahs'Jutan would be one. A planet 1.5 times the size of earth, with over 80% of the surface covered in several Kilometer thick urban sprawl and industrial complexes. A marvel of engineering created over millenia. At least, until the planet gets glassed.
Probably the World Tower Zranta. It was build in the first World (context: The ancient gods made a world, then later disliked it, destroyed it, repeated that process with a second one and then the third stuck). It's a tower reaching to the sky. The gods said to them that if they build this tower they will be blessed with a power that could rival the gods. So they began construction. After a while many people fell off the tower and died. One Guy did not like this whole thing so he went to the woods and found a "wizard" wich was one of the gods in disguise. He taught that guy magic. Before this no one could cast magic. Now the guy helped constructing the tower with magic. They reached the sky not long after and a light appeared. The light said: ,,You people did it. We grant you all the power that was found by one of you". The light granted all of them magic powers. Maybe not power that could rival the gods but the people thought it could. The whole thing is also inspired by the Tower of Babel Story
The Dam. Yes, there are smaller dams but this is the largest infrastructure project on this world (which happens to be a parallel Earth in which a different strain of Homo Sapiens won out). It is the equivalent of Hoover or Glen Canyon Dam on the Colorado but located in original time line Colorado in Glenwood Canyon. This is were I-70 in Colorado has some of its best scenery. Here most of the water from the upper alternate Canyon River (our Colorado) are diverted into the Greenland River (our Rio Grande) to supply the large cities and farms centered around the interdimensional gates found near the Cracks (the Trinity Test sight). The largest city, Gypsum Field, is near our Truth and Consequences, New Mexico and houses around three million people. Sapiens B, as people of a timeline close to ours has labeled them, tends to have more dispersed populations.
Probably Ares colony on Mars. Its set of 5 domes biggest one being around 3km tall and 6km in diameter constructed with lots of internal supports that work as living apartments as well, there is also central Spire building housing atmospheric control center as well as nuclear reactor that provides most of the dome's power. At current time in my universe it is biggest structure possible to be built
**The Gardner** I dunno about "man" made, but it was definitely made and altered, it is a celestial body that generates heat and light as well as a barrier between its domain and the rest of the cosmos, separating space that falls under it's own dominion and laws from the influences of beings beyond.
The single biggest building in the main nation (I haven't really figured out how things will change in the other nations) is Te Whare Hui o ngā Kōmihana (Meeting House of the Soviets) Think of the Palace of the Soviets (canceled replacement for the Kremlin in the 1930s) but instead of being designed by one soviet architect on meth, it was designed by a team of architects that took the whole project seriously instead of one giant propaganda show. 784 Meters tall (minus statue) it is a multi-tier kind of building, similar to how the Burj Khalifa looks but more symmetrical. Built-in the dominant architecture of the country at that period (think a kind of Utilitarian/Brutalist Gothic fusion), The bottom tiers are made out of Stone (Basalt, Limestone, and Granite), while the top parts are the usual mix of glass, concrete, reinforced steel and some lighter stone on the top. The building serves as the location of this Country's version of the Supreme Soviet, White House, and central government office all at once. There are positions amongst the higher floors where CIWS-type devices can be Mounted, as well as a sprawling underground complex that serves as a bunker/command room for the Central Government but is also the headquarters for the OSRI (this country's intelligence service) This is never likely to be used, as due to a previous attack that wiped out the meeting house's predecessor as well as the city it was in, a massive air, land, sea, and space defense program was initiated, and the entire, now rebuilt city is the focus of that (not only due to the meeting house but also to protect a series of Portals that connect this half of the country to its other half, situated in an entirely different universe. The top of the tower is home to a statue, this universe's version of "The Motherland Calls." It is a 100-meter-tall statue made from Unique Minerals and rocks from every SSR. The statue depicts a Woman with a feathered cloak and a Zweihander-style blade pointing toward the Ocean. The Flat space on top of every tier is a mix of Garden and outdoor art galleries, with several statues and exhibitions detailing critical battles, events, and moments in this country's history.
Depends on how you define man-made as mostvfantasy worlds are created thus artificial by gods
Megalopolis of Startess. Startess is an enormous city nicknamed jigsaw. It's tightly packed with illusions of wide open streets, making it appear to look not as condensed as it appears. It's so big that there are entire sectors similar to towns/cities taken over by gangs cause what's there isn't worth the cleanup.
The *Kø̀brik mon Rapat* (Bridge of Swords) is the largest structure on Zùvà Arìànuh. It's a suspension bridge that crosses the Strait of Swords, the entrance into the Great Blue Bay on which sits the world's largest city *Korat Bàkalif Kanalø̀* (pop. 720,000 as of ST1020). Constructed between ST0072 and ST0073, it's just over a kilometre in length, its two towers reach 302 metres in height, and it's painted a pleasant shade of blue. It links the city proper with the commercial harbour district and northern suburbs. The upper deck carries foot and cycle traffic with a lower deck for light rail, freight and emergency vehicles. The bridge takes its name from the strait, which in turn was named after three rusted swords of unknown origin that were found at the base of its southern cliffs by the first survey team to visit the area (they now reside in the city museum). The bridge is regarded as a symbol of *Korat Bàkalif Kanalø̀* and appears prominently on the city flag. Locals are generally pretty smug about it being over three times taller than the next tallest structure on the world, the *Oliskuh Konsòtium* in *Korat Balzad Zùvàrùn*.
Nova city, Covering all the south pole of nienztknownowschauta
The Wreath. An “orbital ring”. A titanic international space station circumventing the entire Earths equator, located in low earth orbit. It has multiple purposes, but it main one is being a jumping off point to space. It has a multitude of space elevators attached to it around the globe, and acts like a combined launch platform, dockyard, habitat and transport network.
The Black Book of SRL (Saral) is literally a giant stone book with the entire (equivalent of) 7 bibles inside. Usually said bible (the Jilam) is split into ten books but the Black Book condenses all of them into a 50, 60ish ft tall monolith.
At the center of the dragon world is their capital city, and around the whole city is a giant facility called The Ring, which is a colossal building surrounding the capital city itself. It serves many purposes and is divided into different parts that serves different purposes, like a hospital part, a portal center and many other workplaces for the dragons.
I like to cram gargantuous stuff so ancient as to dwarf any character or their current era's architectural/engineering achievements, in my worlds, so there's something of a list... Not that I ever actually made a list or anything, so to speak, mind you. I don't think it's so much amazing rather than me just going into the ridiculously sized, nor is it completely detailed, but: (PS: I'm being vague about the species/race/people because it's moreso a template of sorts which I adapt, like other world elements, to the settings I include it in.) The largest I ever explored would have to be an entire, gigantic artificial world with a solar system harnessed within it. A pulsar star encased in a dyson sphere core at its center whilst the habitable worlds orbiting inside are cultural hubs and home to the society's elites due to the natural nature of the worlds and the scarcity of living space permitted on their surfaces, and other, uninhabitable planets, well, they don't exist as they have been exploited to their cores' marrow. The artificial world doesn't really have a name, as it were, it's usually referred to as "the crust/shell/shield/surface's surface" or other such. It was built during a time when projections were made that nearby systems would be turbulent due to several stars would enter new ages or die in succession. To soak and reflect whatever would come the system's way. Rather than protecting merely the habitable worlds as one would typically focus on due to resources, they encased the system as a whole due to their people habiting nearly all planets, at the time, whether on them or orbiting from stations that were vital at the time; as well as their people's overall deep galling spite. They simply felt like throwing a middle finger at the universe's ways in unison and laboured to achieve the impossible, even given their already advanced technology at the time - which the project's duration furthered, in a sense it was akin to a nuclear arms race during WWII. Time after these dangers passed, the shell began being reworked to accomodate life, where the lower echelons of society would eventually be confined to. Those living in the natural worlds within are called low-lives by most crustlings, as a play on their position in the structure of the star system; and the elites similarly call those living on the shield low-lives. The dual use may lead to confusing and awkward moments of camaraderie when two individuals complain about low-lives together upon meeting in a pub before realising they refer to one another.
Don't know what exactly counts. A huge wall between mountain range and the ocean which was built by an empire to control trade, the migration and to protection against invasion. Originally the border were river but cities, but they grew too large on both sides of the rivers necessitating a new artifical border. It was damaged during an earth quake and then abandoned. A City district carved into a mountain which over time developed into one huge structure instead of many buildings. The city was right next to dormant vulcanos and a river system flowing from the same mountains the wall was built. Due to the ashes the surrounding land was very vertile. The specific place of the city was originally a natural river crossing with a lot of trade. "Razed" by invaders after being damaged by same earthquake which damaged the wall. Because Toxic minerals from eruptions linked to the earth quake plus actively poisoning the ground by invaders the city was abandoned and not rebuild. There is also a long channel, farther in the south which was built to be able to create a new trade route from the western empire mentioned earlier to be connected to major cities/empire other side of the continent without going through dangerous arctic waters or a very long land route. After the fall of the great trade empires it became a border instead of a trade route. I'm not creative with names, so don't have any names yet and called just by what they are. High distric of the capital of the first western empire, great wall of the first western empire and great southern channel.
Oldest _remaining_ manmade structure is a centuries-old military base, mostly buried under a desert. Infrastructure and engineering in my world haven't recovered enough to build skyscrapers and things like that
Depends on what you mean by "manmade" If you mean specifically made by humans, the largest single structure is the ancient voidship at the center of the Capital, which is a whole city unto itself, especially after being build upon by multiple subsequent civilizations. I could also just say the capital in it's entirety, but that's more multiple structures in my mind. If you count made by aliens, and you count careful cultivation and pruning to guide the growth of a giant mat of plants (or plantlike "animals" in this particular case) as "making" something, then the Noenlands. Literally an entire continent created through generations of massive scale projects, including building support structures to guide the growth in specific ways, like the megastructure equivalent of a lattice for grapevines. And if you count gods, then the planet itself is actually a giant magical mechanism. The crust of the planet is pretty thin, and everything inside that is artificial mega structure, long since overgrown and abandoned, and now home to a whole subterranean ecosystem and civilizations. I think this kinda qualifies for the question since most planets in universe are naturally formed, this one just happened to be literally built and is actually a machine on the inside.
If we’re a bit liberal about “human” the world of Elysium (blessed home of the Gods, blah blah blah) is encircled by a single equatorial ring pierced by sixteen orbital towers. We can be a bit less liberal and look at the Colonials. (Like most of the Elysians they are near humans but they aren’t ruled by posthumans) The colonials never developed FTL drives so when they realized their star was destabilizing they built vast colony ships. If we’re strict about what’s human, perhaps the sixty kilometer dome protecting the city of Verneville on the Moon.
There's a space station that was built during the initial colonization of the solar system as the magitech equivalent of a fuel depot and later abandoned as technology advanced and people no longer needed to refuel in the middle of trips. A group of pirates took it over and, shortly before becoming too big of a nuisance to remain under the radar, decided there was more money in being Space Monaco than Space Port Royal, transforming into a haven of organized crime and vices. During the chaos of the abandonment of Earth they expanded a great deal, buying the ramshackle ships most of the refugees used to get off of the planet for pennies on the dollar and turning them into thousands of new modules and habitats. Today - or, if any of my players are reading this, *the last you remember* - the population of Waypoint sits at a respectable 1.2 billion, making it effectively the third largest city-state in Human space, though it only accounts for around three percent of the solar population and a much smaller fraction of the total population of Humanity. It's still more or less run by the mafia, though.
The Monarch's Visage. Appears to be a really, really enormous ziggurat with 4 towers on each corner, and a palace right on top. A city of the North is equal to 6 Earths in area, and this one structure's area is 85% of the central capital city (which is about 10% bigger than the other surrounding cities). Designed to hold in a hundred septillions' worth of people at one time, this structure is both the seat of influence of the High King of Karinia, a last bastion of the people, and a city in and of itself. Within the first 300,000 floors from the ground up, are living quarters, and farms with plants that feed straight up on mana and is safe to consume, and wyverns, a drakeborn livestock kept and eaten like Earth's chicken. Staple food of the North. 300,000 more floors have more living quarters, and a few hundred training grounds, half of which have forests in them. 400,000 floors right after those 600,000 are more living quarters (btw it isn't a chore to get in and out of a living quarter, portals exist, and those have basements for storage and is rather spacious, maybe as spacious as the area of a five star hotel), and an arena where blood can be spilled but no one dies. Sometimes the High King, the Kings, the High Lords, and Lords and generals would demonstrate new skills there for the people to watch. Btw this place has its own server, and yes the internet exists because it's been 5 trillion years when this building was completed, same with lasers and stuff. 200,000 floors of purely living quarters and some restaurants exist in at the topmost half of the third tier. The Red Throne Room, which is only used by the High King to sit around in or pass his judgement and pass laws, the Throne Room has no pillars and is vast, with light taking a second to bounce around in the room. Found on the middle of the actual palace's first floor. The Drakerest, which is where dragons being cared for by the High King are kept, is a floating tower with no roof (the usual towers you see, it has a turret but no roof) and many entrances the size of well, dragons. The right wing of the palace has the Monarchial chambers, a war room, a library, , some study rooms, and central server rooms. Out front is the Left garden, where herbs are grown, and can be used as a training ground or a place to relax. Has a lake the size 90% of an earth. The left wing of the palace has attendants' quarters, maids' quarters, butlers' quarters, chefs' quarters, an armory, blacksmith's, a forge, guest rooms, a massive feast hall, a weaver, and a tailor. There's also an orchard here and flower gardens. Both left wing gardens and right wing gardens have fountains and is essentially a park as well. The four towers. One is the Martial Tower, where the greatest melee weapon wielders are nurtured. There's a floating fortress right next to the top floor of this tower as well. The other behind it is known as the History and Cartography Tower, where all knowledge recovered and records about the history, geography and what the world used to look like and now looks like are kept. Nurtures scholarly adventurers. The third tower across this is the Arcane tower, where everything magic is improved upon, studied, and new spells and runes are discovered. Is the seat of the Magus Ultimar, and houses the greatest mages in life and death. Last but not least is the Forge tower, where armors, mechs, lasers, and other usually militaristic constructs and items are made. Right below the entire palace are the Inexhaustible Mines, named for what happens after you dig out a single ore, ten more appear right behind where you got the ore. Favored dwelling of dwarves and kobolds; children of trolls and dwarves, outcasts in ogroid culture and society.
Ive been thinking about in one of my world having the dwarves hallow out an entire mountain to build a giant organ instrument in the mountain it is also the most complex instrument every designed it actually requires 3 people to play it and they have to be in perfect harmony its basically a one instrument orchestra
"Manmade" is actually the Gealtian Empirial Palace. The Largest "Elvenmade" are the dozen spires around the world that make the palace look like a fort.
The void engine, created by a fallen machine empire in order to destroy the walls of reality to find their none existent creator.
The story takes place across several eras thousands of years apart and in each of these eras, one of the races called the Osyci have been building a massive, black wall across the entire planet. None of the other races know its purpose but the Osyci do not care who or what is in their path. It will be built. If they mean for it to go through your kingdom and you take issue with that, you may fight them and you will lose because they will fight for an eternity if needed until there is no further resistance to the wall being built.
The white flame tower is 150m tall but it's only the visible part of a vast network of gaz and geothermal water covering the thousand Km of the Fallen Empire of Aïtsara. The goal of the structure is to provide power and heat for all citizen, industries and greenhouses. Some part of the network are millennia old and need a special engineering team know as the "Piper". The Piper are part of the army as some part of the network has fallen into wild territory and need some "killing" ability. If for a reason or an other the network suffer a critical failure the entire continent will became non suitable for life as temperature rarely go above 0°C. The Fallen empire is the most advanced nation as the rest of the planet is on late antiquity period (IV-V AD).
The tower of Babel. Actually a pyramid. The base [was] 5×5 km (3.1×3.1 miles), and it [stood] 3,180km tall (1.9 miles) The tower was the final construction built by humans, dwarves, and giants as a collective. After its completion, around 4.465 billion years ago, war broke out over "ownership." The Giants did the heavy lifting, they argued. But how could they without the ingenuity of the humans, the humans would say. Had the dwarves not quarried the stone, there'd be no tower... What should have been a symbol that they could accomplish anything if they worked together became a symbol of animosity. After a war with no clear winner, the groups went their separate ways, even so much as to develop separate languages. Edit: It *stood* 3,180km tall at the time off the setting. It was destroyed when Theia crashed into the earth some 4.46 billion years ago.
I'm debating it, but I think, in **Elenon**, it's Rixadel Fortress
If you're making something up off the top of your head right now to submit to this thread... Upvote me to anonymously advertise and "mood fam" the others who did the same. The mountain of your upvotes might become the largest structure on this thread... and those who wander these forgotten halls when we are nought but memories on WayBack, will ponder with casual indifference as to who we all were...
Probably 'The Tower', if we're counting Dwarven buildings as 'man-made'. It sits on a plateau with a carved staircase and has an octagonal base with sides of 200m long giving it an approximate area of 1.93×105m² at the base. Its age is unknown and the name of the architect and the original design specifications have been lost to time, so the Dwarves are essentially just freestyling it for now. It's so big it may never be completed, for the building materials, labour costs, maintenance costs, logistics, trade routes may prove too expensive or unmanageable in time. It may even outlast Dwarven civilisation itself before it is finished, if it even can be. It is the number one marvel of their people and it is a great honour to be nominated to live and work in the city that has sprung up around it to feed its steady growth. Every clay brick is stamped with the name of its maker and date in cuneiform before firing, making it a civilisational tapestry of countless names and lives across unnumbered lineages. To be immortalised forever more in the most impressive architectural wonder in the world to ever be built is a privilege to be cherished until death.
Me upon reading the question: Oh cool, I've got a giant ziggurat! Other redditors: I've been preparing myself for this question for ages, I know exactly how many meters tall it is and how it compares to other structures.
Katamari habitats. They destroyed the biome on their homeworld in an accident that released a nano phage into the wild. Now there are about 100 million left, mainly living offworld or in large O'Neill style habitats. Out of necessity the Katamari developed far better tech to fabricate space habitats, and are in the process of revolutionising the industry. Katamari engineering firms do a lot of consulting work in this space now.
One of the largest structures built by humanity in my world is the planet Earth. After space trees tore the Earth into pieces, humanity took the planet and glued it together like fine China. It's true that many pieces of Earth were lost to the abyss, but much of the planet was rebuilt.
The Vürian Tunnel Networks. It is a connected tunnel system that spans under a whole continent that makes up 1/7th of the worlds total land mass. It was made by a precursor race which the current inhabitants - the Iwegi - occupy a small portion of it, and in their equivilant of modern day they are still trying to map out its full extent. One that is not in ruins is the Baityian College of Edoic studies Super Conductor. It was designed by a revolution leader turned scholar Bertha the Blind who is a legend in her own right, a tower that stretches 200m high into a basement that stretches a whole kilometre under ground with a series of tubes firing particles at the speed of light, not too dissimilar to the hadron collider but with many more functions. The conductor led to the discovery of how edoic manipulation (or magic in laymans terms) can be used to manipulate ionising radiation without causing too much harm to the body.
A space station built in the skeleton of a long-dead dragon.
I really like the idea of a bridge over an isthmus being the largest manmade structure in the world. Apparently even making them out of wood with Babylonian era tech there's not really any upper limit on how big such a bridge could be because you could essentially do what ants do and build a giant mound of sticks over the gap. That would give you a crazy arch that is basically a filled in semicircle, and so it is at the midpoint half the height of the span it crosses, and then at the edges is near vertical unless you built some offramps to reduce that which would increase its length yet further. But yeah no upper limit on size. I'm just trying to work out at what size it becomes cartoony. This isn't very scientific but I'm thinking .... the bosphorus is 700m and that looks doable. So I'm thinking a raging tidal isthmus between steep sheer 100m cliffs, a huge mound of a bridge that towers 500m high at its peak, and then long sweeping up and down ramps that make its total length well in excess of a kilometer. It's understructure is an absolute thicket of wood, maybe looking more like thatch than anything else, although each element of it is a full grown tree trunk log. But while the structure is thick, insanely thick, it does still stretch up to clear the straits by several hundred meters at the midpoint, allowing ships to pass. And of course both the over and under sides of the bridge would inevitably become towns of sorts. Or rather, given the size, have multiple towns and villages scattered within them. Not to mention at any given time parts of this bridge would be rotting and collapsing and being replaced, but not always in time to prevent local cave ins, with fresh timber.
Large Block of Tungsten.
A key character in my universe is an alien artificial intelligence whose physical structure occupies the region of, and is the cause of the significant gravitational anomaly known as, the Great Attractor. The AI is known to humans as Xerris, who appears as a featureless, black, sphere with a diameter some several million lightyears across. The structure is also “hyperspatially transient” and exists within multiple universes simultaneously.
Strictly "man"made would probably be the Stone Forest, an array of several hundred pillars that once held up a now-collapsed large concrete structure that used to cover an entire valley some few thousands of years ago. Nowadays it's mainly a digsite, considering it's the largest accessible site of ancient relics. If something built by the God of Craftsmanship counts, then it's the Black Glass Tower, a massive building large enough to house a city's worth of people just in the bottom quarter of it. The deity in question lives in the penthouse with his family, while the other residents are mostly clergy, officials, and vendors - support staff to handle the constant influx of tourists and pilgrims.
Does the canal-system count? Back when the aliens were using the planet as a supply base, they had a railroad. While the rails were recycled, the ballast made it a good cart-road. Unless it's something boring like a dam, my world's largest structure would probably be a folly. Native castle design wouldn't really get past the motte-and-bailey when mages are hell-bent on making warfare into a sportsmatch with casualties. Pretty much defensive fortresses would leap straight into fairy-tale castles.
The great barrier walls that surround every major city.
**No Mans Land 2210** The Apollo-88 solar power plant. Built on what was once the farmland south of the Salton Sea, after advances in vertical hydroponic farms rendered them obsolete and wasteful, Apollo-88 is a 100-sq mi complex of heliostat reflectors built around dozens of receiver towers, as well as fields of classic photovoltaic solar panels. Everything about the place is made to generate electricity. Every building has panels on the roof and walls, the parking lots are shaded with solar panels. Even the floors that workers walk on is lined with piezoelectric materials so that they make electricity simply by walking about in the course of their duties. The Salton Sea itself is used as a heat sink, helping to cool the liquids heated in the receiving towers in the process of generating steam to turn turbines. Apollo-88 generates over 20GW of electricity, rivalling the output of the few large-scale fusion plants still in operation. However, Apollo-88 has a much larger footprint than any fusion plant. The four large-scale plants in the Nevada-California two-state area would fit easily within Apollo-88's territory... with room for a dozen more. Apollo-88 *should* be a juicy target in a post-apocalyptic world. But it's not. Electricity is seen as such a vital resource that any wannabe wasteland tyrant who wants to make Apollo-88 her throne and palace is met with fierce resistance, not only from the cities, but from allegiances of wasteland groups who normally wouldn't have anything to do with each other at best or are even hostile to one another at other times. These allegiances never last, dissolving once the plant is safe and reforming if it ever comes under threat again.
The stellar ring colony around the star "YR102-15700" (official name: [P.1F-43.YR102-PRA.157001.LAO-1]), commonly known as Praavia-Laotrea or Laotrea. A colossal orbital ring, over 35 million kilometers long, that extends around the entire star. The ring is divided into four layers: 1. The first one, the “Sunny Side,” is covered with layers of gold, silver, and aluminum shields that have been polished to a reflectance rate of nearly 100%. 2. The second layer is a ring in the form of a tube with a counter-rotating, fast-moving magnetic fluid inside. 3. A network of superconductors extending from the first to the fourth layer, with long, shielded radiator “cables” is classified as the third layer. 4. Finally, the fourth layer is the actual colony itself. This gigantic configuration allows the colony to dive deep into the star's corona and as close to the photosphere as possible. This, in turn, is done to better direct the large swarms of solar satellites, trigger controlled CMEs and solar flares, and intercept the magnetic and solar winds of Praavia-Laotrea. The stellar ring colony serves as the main supplier of energy and matter to the star system. It extracts 1000 times more metals and minerals than any other celestial object or station/habitat within 1 ly of it COMBINED, while also providing enough plasma to keep the civilizations of Laotrea running for hundreds of millions, if not billions, of years. Finally, it also serves as the main hub for repairing the SCH-Trustees and Sattelite Swarms, as well as transferring energy to interstellar stations and accelerating ships to other stars.
In one of my world, there is no human or humanoid, but only bugs, dragons and birds. Bees are one of the species in this world, know for their skill in navigation and building. At the beggining of the world, the first Bees Queen traveled to a far-away plain to start the first Beehive. Because most of the bees is around 1 meter/ 3 feet long, the Beehive is HUGE, even after the creation of new beehive (all named after the distance and direction to the main Beehive). The Beehive and its network of smaller beehive, coupled with the navigation skill of the bees, have made travel in the plains easier for bugs, until history separated the network between two ennemies bloc: the Good Community bloc and the Crow-Dragon bloc, where the Beehive is because they welcomed Egamel and the Spiders during their exile out of Good Community.
Was, it was destroyed a few milenia ago. The Tower of Derual, kwown only as the Hollow Tower now, it was a gigantic construction of about 3km radius and 1km tall that serve as fortress and City to all the knowledge, guarde by the ancient god of Wisdom Derual. After a War where the Golden Emperor and the Dragon Empire tried to subdue everything, they seriusly damaged the tower, leading to it falling apart some centuries later.
New Alexandria. Created a few decades before the Great War or Godscourge. Humans had finally begun to rebuild society from ground up. They gathered all the information about the old world possible, music, birthday videos, literature and even voicemails. Alexandria was so large that a Draegkon could fly inside it for a month and still not hit the ends. It took up three continents of circumference. A marvel of Havian engineering, coding, bookkeeping and resilience. It was so beautiful it made even Odin cry. He soon got usurped by one of his children. We never learnt who. Thoth was their patron god and aided, so did the last remaining Norse dwarves who went extinct—someone had been silently executing them. Humans were easily more advanced than they had been before they nuked themselves dead. The Library was supposed to be public domain, society was booming again and humans were finally changing for the better. Athena burnt it down to nothing. Some say that is when the war truly started. Sadly humans were set back to the 20th century in terms of progress. Radio waves were obsolete on Havia due to the high concentration of reality warping radiation and Gaia had grown so much that there were mountains larger than our "moon". Humans stood no chance and forever mourned the death of Alexandria. Now it's a myth.
The Condenser Wall probably. A 200 meter thick wall standing at 1200 meters of height containing enormous oil fired coils with coolant and fueled by five tandem wired nuclear tokamak engines tasked with cooling an area comparable sizewise to the City of Los Angeles or the Entire Bay area down to freezing point. The condensation also cools down a nearby pine forest and supplies it and agricultural areas with abundant water.
It’s the city of Zirkar. It’s an orc stronghold in the middle of the desert. It’s actually a giant three spired tower that is as tall as a mountain; it also has an extensive tunnel network underneath it. It is home to 100,000 orcs.
Posterus. It’s a man made sky island that creates futuristic technology and medicine before sharing it with the rest of the world
The black vault, a large repository of old tech made by the aleph roughly 4 to 5 solor systems in size, and due to the dangers of all this tech it is extremely well defended by autonomus systems despite being eons old at this point.
Not manmade but there is a structure named Cloches. It's described as a palace of bells born of a reef and dressed in the ocean's bluest shell, where a clock delivers the message of the silver sun down to those below. It serves as a dungeon throughout an entire arc in my novel series. It's a labyrinth of 12 gardens, each with the goal of forcing those in pursuit of its apex to give up and accept their fate. That fate being an inevitable death when Cloches' clock counts down from midnight to back again. It's a lot to get into, but my world, and series at this point, centers around my protagonist's journey through the new world after she brings about the end times in the previous one. She has no recollection of her past life, but when she left it, she left behind six brothers, of sorts, who also awaken to this modern age. Only their minds have been twisted and their forms followed, resulting in each manifesting as a different "final boss," or whatever you want to call them---again, a lot to get into. Cloches is the second youngest brother, reborn as the palace, his mind set on delivering a "cure-all to life" as he refers to it. An end to struggle. Death. Swift and unavoidable.
The Night-mother's tower where the high priestess of the biggest human religion in the city the religion started resides.
Rail Flower. It would be ridiculous to call it a rail yard when it spans farther than Pangea. In addition to that the trains themselves are larger than that of the Burj Khalifa itself at times. On a planet the size of the current observable universe, these trains travel at 99% the speed of light. Yes, sure, you have FTL as an option, but that requires you to get OUT of the atmosphere first, and do you have the money for a ticket to the space elevators? didn't think so.
The Red Tower. Home to the Red Wizards of Sunhold, the Red Tower was a structure built by the wizards who study the dark magics shunned by the majority of Sylvarra and Ebonreach, and is used to maintain the dark magic they practice. Without proper skill, or knowledge, casting spells that are considered “dark magic” can become uncontrollable and unmaintainable which could result in many different outcomes ranging from the death of one individual, to hundreds, to crushing a castle or even sinking an entire landmass. The wizards built the tower and created pocket dimensions they access using portals which allow them to practice these magics in order to study how to defeat them without the risk of someone losing their life.
The generally largest structure is the Prescott Basin Mine, a mine dedicated to supplying most of the world’s rare elements, and Thiaenium, the element for magic. It goes around 47 miles down into Pramaria’s mantle, where most thiaenium is located. The largest “structure” structure, is 119 Lucio Street, known more commonly as “Lucio Tower”. It is the largest skyscraper in the world, and is atone to the WTC in Manhattan. It hosts galactic meetings, is a huge center for trade and commerce, and hosts many other businesses and apartments.
Probably "The Black Keep". It's a large asteroid base consisting of several asteroids. It's purpose is to airstrike strategic locations as well as deploy specialized troops
The BRIDGE.
The Playground. Playground was builded by gnomes as a bunker but Kupid decided to turn their bunker into a heaven. On the outside, Playground is a massive building that is literally "The Square". It is 200 kilometer wide on every side and 15 kilometer tall. But on the inside, its infinite. Thanks to the Kupids god powers
I would have to say my ring world (the Shikar Ring). It stretches all the way around the local star. Most of it is uninhabitable though. It's left over from the old human empire before they almost got whipped out. Now the current empire (the Shikar Imperium) is trying it's best to scrape together the remnants of what humanity once had. The so called Ancestral Empire was really into building massive constructs. So now the galaxy is littered with the husks of these wonders.
The all speaking tower of king Morydd. A tower made by his hand allowing him to preach to every living soul on earth. It extends over the atmosphere on a base of rock that spreads through the land. At the bottom are bridges that connect the tower to every continent.
The Aether Apparatus, found deep within a Major Dwarven Ruin, it's a massive pillar like structure, while the actual size remains unknown (more then two miles long and half mile wide), it generates a pulse of uncontained Aether Energy every so often to the top. It's believed to been a power source or a weapon for the Dwarfs before they vanished. Aether Energy is highly dangerous as it causes various effects to life so every time it pulses anyone within the large room with it experiences intense pain, magical feedback, major burns along your body and if you happen to be standing close enough you'll get vaporized.
Alien facility under the ices and landmass of Antarctica, covering almost entirety of the continent with it's rooms, halls and tunnels. It is partially in ruins and its exact function is unknown, aside of clear connection to the Days of Oblivion, it appeared during.
Big. Fucking. Bridge. Made to cover the gap between two close mountain peaks separated by a massive cavern. An order from a dwarven king, with a lot of Orc contractors as well. Amazing sight to behold, absurdly large. And built to withstand anything! (Halfway through construction, things went wrong and resulted in mass death of the construction workers, after that happened, they just continued building it. Many More people died for various reasons. but it didn’t collapse this time)
Haven't revealed the hole story yet (not sure about the numbers too) but there was royal cities ruled by certain kings who desire (or manipulated) to reach to the sky to meet with gods. With this purpose they forced their servants to levitate the land around their castle to build a tower under. Promised their servant to when they reach to gods they will ask them there too. But so many years past servants keep building these massive pillars and no one knows what happened to these people who stuck on the top of the towers. (except me eheh)
The Dead Wall. So in the east there are three cites (roughly analogous to Prague, Vienna, and Budapest). Prague is ruled by a Lich, Budapest is ruled by a Vampire Lord, and Vienna *literally* the ghost town where they fought their war against each other. Well, there's another city (roughly analogous to Rome) that built a 200+ milt long wall on their eastern frontier to monitor the Dead Lands and to ensure that no dead or undead creatures make their way toward civilization.
Giant submarine’s known as Fatherships. It’s basically a continent sized vessel that can travel underwater, as well as fly like a spaceship.
The Vision Tower, a tower soooo tall that if you went to the top of it you could see the whole world (My world is flat). The tower was made to spy on other nations by the Empire of the Center. The tower is also used as a giant net to catch flying lobsters and birds that the people below eat.
Probably the almond farms (entire terreformed worlds dedicated to almond farming).
It's a pretty young world so, for now, the biggest structure is the Tomb of Brian. Legendary chieftain and allegedly son of a god