A megastructure is a very large manmade object, though the limits of precisely how large this is vary considerably. Some apply the term to any especially large or tall building.

Some sources define a megastructure as an enormous self-supporting artificial construct.
Other criteria such as rigidity or contiguousness are sometimes also applied, so large clusters of associated smaller structures may or may not qualify. The products of megascale engineering

Megascale engineering

Megascale engineering is a form of exploratory engineering concerned with the construction of structures on an enormous scale. Typically these structures are at least 1,000 kilometers in length—in other words, at least 1 megameter, hence the name...

 or astroengineering

Astroengineering

Astroengineering is the construction of megastructures in space by technologically advanced beings. It is a form of megascale engineering. Typically proposed feats of astroengineering are on the scale to remake an entire stellar system....

 are megastructures.

Most megastructure designs could not be constructed with today's level of industrial technology.
This makes their design examples of speculative (or exploratory) engineering

Exploratory engineering

Exploratory engineering is a term coined by K. Eric Drexler to describe the process of designing and analyzing detailed hypothetical models of systems that are not feasible with current technologies or methods, but do seem to be clearly within the bounds of what science considers to be possible...

.
Those that could be constructed easily qualify as megaproject

Megaproject

A megaproject is an extremely large-scale investment project. Megaprojects are typically defined as costing more than US$1 billion and attracting a lot of public attention because of substantial impacts on communities, environment, and budgets. Megaprojects can also be defined as "initiatives that...

s.

Megastructures

Megastructures (architecture)

Megastructures are an architectural concept popularized in the 1960s where a city could be encased in a single building, or a relatively small number of buildings interconnected together....

 are also an architectural concept popularized in the 1960s where a city could be encased in a single building, or a relatively small number of buildings interconnected.
Such arcology

Arcology

Arcology, a portmanteau of the words "architecture" and "ecology", is a set of architectural design principles aimed toward the design of enormous habitats of extremely high human population density. These largely hypothetical structures would contain a variety of residential, commercial, and...

 concepts are popular in science fiction.

Megastructures often play a part in the plot or setting of science fiction movies and books, such as Rendezvous with Rama

Rendezvous with Rama

Rendezvous with Rama is a novel by Arthur C. Clarke first published in 1972. Set in the 22nd century, the story involves a cylindrical alien starship that enters Earth's solar system...

by Arthur C. Clarke

Arthur C. Clarke

Sir Arthur Charles Clarke, CBE, FRAS was a British science fiction author, inventor, and futurist, famous for his short stories and novels, among them 2001: A Space Odyssey, and as a host and commentator in the British television series Mysterious World. For many years, Robert A. Heinlein,...

.

In 1968, Ralph Wilcoxon defined a megastructure as any structural framework into which rooms, houses, or other small buildings can later be installed, uninstalled, and replaced; and which is capable of "unlimited" extension.
Many architects have designed such megastructures.
Some of the more notable such architects and architectural groups include the Metabolist Movement

Metabolist Movement

In the late 1950s a small group of young Japanese architects and designers joined forces under the title of "Metabolism". Their visions for cities of the future inhabited by a mass society were characterized by large scale, flexible, and expandable structures that evoked the processes of organic...

, Archigram

Archigram

Archigram was an avant-garde architectural group formed in the 1960s - based at the Architectural Association, London - that was futurist, anti-heroic and pro-consumerist, drawing inspiration from technology in order to create a new reality that was solely expressed through hypothetical projects...

, Cedric Price

Cedric Price

Cedric Price was an English architect and influential teacher and writer on architecture.The son of an architect, Price was born in Stone, Staffordshire and studied architecture at Cambridge University Cedric Price (11 September 1934 – 10 August 2003) was an English architect and influential...

, Frei Otto

Frei Otto

Frei Paul Otto is a German architect and structural engineer.- Life :Otto was born in Siegmar . He studied architecture in Berlin before being drafted into the Luftwaffe as a fighter pilot in the last years of World War II...

, Constant Nieuwenhuys

Constant Nieuwenhuys

Constant Anton Nieuwenhuys was a Dutch painter, and one of the foremost innovators of Unitary Urbanism. In 1941, he became deeply interested in the work of Paul Cézanne, Cubism and German Expressionism....

, Yona Friedman

Yona Friedman

Yona Friedman is a Hungarian-born French architect, urban planner and designer. He became famous in the late 1950s and early 1960s, in the so-called age of megastructures.-Early years:...

, and Buckminster Fuller

Buckminster Fuller

Richard Buckminster “Bucky” Fuller was an American systems theorist, author, designer, inventor, futurist and second president of Mensa International, the high IQ society....

.
This type of framework allows the structure to adapt to the individual wishes of its residents, even as those wishes change with time.

Other sources define a megastructure as "any development in which residential densities are able to support services and facilities essential for the development to become a self-contained community".

Existing

There are structures that may be considered megastructures, such as

• The Great Wall of China
  Great Wall of China
  The Great Wall of China is a series of stone and earthen fortifications in northern China, built originally to protect the northern borders of the Chinese Empire against intrusions by various nomadic groups...
  
   is a human-built megastructure, a few meters wide and 3947 miles (6,352.1 km) in length, about 4975318 yd2

• The Rice Terraces of the Philippine Cordilleras
  Banaue Rice Terraces
  The Banaue Rice Terraces also called Payew, are 2000-year old terraces that were carved into the mountains of Ifugao in the Philippines by ancestors of the indigenous people. The Rice Terraces are commonly referred to by Filipinos as the "Eighth Wonder of the World". It is commonly thought that...
  
  , a 10360 square kilometres (4,000 sq mi) sprawling agricultural landscape carved in the mountains by free tribesmen of Ifugao
  Ifugao
  Ifugao is a landlocked province of the Philippines in the Cordillera Administrative Region in Luzon. Covering a total land area of 262,820 hectares, the province of Ifugao is located in a mountainous region characterized by rugged terrain, river valleys, and massive forests...
  
   some 6,000 to 2,000 years ago.

• Skyscraper
  Skyscraper
  A skyscraper is a tall, continuously habitable building of many stories, often designed for office and commercial use. There is no official definition or height above which a building may be classified as a skyscraper...
  
  s represent our current state-of-the-art in large structure engineering. (See the list of largest buildings in the world.)

Networks of roads or railways, and collections of buildings (cities and associated suburbs), are usually not considered megastructures, despite frequently qualifying based on size. However, an ecumenopolis

Ecumenopolis

Ecumenopolis is a word invented in 1967 by the Greek city planner Constantinos Doxiadis to represent the idea that in the future urban areas and megalopolises would eventually fuse and there would be a single continuous worldwide city as a...

 might qualify.

Proposed

• Atlantropa
  Atlantropa
  Atlantropa, also referred to as Panropa, was a gigantic engineering and colonization project devised by the German architect Herman Sörgel in the 1920s and promulgated by him until his death in 1952...
  
  , a hydroelectric dam to be built across the Strait of Gibraltar
  Strait of Gibraltar
  The Strait of Gibraltar is a narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Spain in Europe from Morocco in Africa. The name comes from Gibraltar, which in turn originates from the Arabic Jebel Tariq , albeit the Arab name for the Strait is Bab el-Zakat or...
  
  , and the lowering of the surface of the Mediterranean Sea
  Mediterranean Sea
  The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
  
   by as much as 200 metres.

Stellar scale

Most stellar scale Megastructure proposals are designs to make use of the energy from a sun-like star while possibly still providing gravity or other attributes that would make it attractive for an advanced civilization.

• The Alderson disk
  Alderson disk
  An Alderson disk is an artificial astronomical megastructure, like Niven's Ringworld, or a Dyson sphere. The disk is a giant platter with a thickness of several thousand miles. The sun rests in the hole at the center of the disk. The outer radius of an Alderson disk would be roughly equivalent...
  
   is a theoretical structure in the shape of a disk, where the outer radius is equivalent to the orbit of Mars or Jupiter and the thickness is several thousand miles. A civilization could live on either side, held by the gravity of the disk and still receive sunlight from a star bobbing up and down in the middle of the disk.
• A Dyson sphere
  Dyson sphere
  A Dyson sphere is a hypothetical megastructure originally described by Freeman Dyson. Such a "sphere" would be a system of orbiting solar power satellites meant to completely encompass a star and capture most or all of its energy output...
  
   (also known as a Dyson Shell) refers to a structure or mass of orbiting objects that completely surrounds a star to make full use of its solar energy.
• A Matrioshka brain
  Matrioshka brain
  A matrioshka brain is a hypothetical megastructure proposed by Robert Bradbury, based on the Dyson sphere, of immense computational capacity. It is an example of a Class B stellar engine, employing the entire energy output of a star to drive computer systems...
  
   is a collection of multiple Concentric
  Concentric
  Concentric objects share the same center, axis or origin with one inside the other. Circles, tubes, cylindrical shafts, disks, and spheres may be concentric to one another...
  
   Dyson Spheres which make use of different wavelengths of light.
• A Stellar engine
  Stellar engine
  Stellar engines are a class of hypothetical megastructures which use a star's radiation to create usable energy. Some variants use this energy to produce thrust, and thus accelerate a star, and anything orbiting it, in a given direction...
  
   either uses the temperature difference between a star and interstellar space to extract energy or serves as a Shkadov thruster.
• A Shkadov thruster accelerates an entire star through space by selectively reflecting or absorbing light on one side of it.
• Topopolis
  Topopolis
  A topopolis is a tube-like space habitat, rotating to produce gravity on the inner surface, which is extended into a loop around the local star. Topopoli can be looped several times around the local star, in a geometric figure known as a torus knot. The concept was invented by Pat Gunkel and...
  
   (also known as Cosmic Spaghetti) is a large tube that rotates to provide artificial gravity.

Planetary scale

• An Orbital is a space habitat similar to but much smaller than a Niven Ring. Instead of being centered around a star, it is orbiting a star, thus its diameter is typically on the order of magnitude
  Order of magnitude
  An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. In its most common usage, the amount being scaled is 10 and the scale is the exponent being applied to this amount...
  
   of a planet. By giving a tilt to its orbit, there's a convenient day and night experience on its surface.
• Globus Cassus
  Globus Cassus
  Globus Cassus is an art project and book by Swiss architect and artist Christian Waldvogel presenting a conceptual transformation of Planet Earth into a much bigger, hollow, artificial world with an ecosphere on its inner surface...
  
   is a hypothetical proposed project for the transformation of Planet Earth into a much bigger, hollow, artificial world with the ecosphere on its inner surface. This model serves as a tool to understand the World's real functioning processes.
• Cloud nine
  Cloud nine (Tensegrity sphere)
  Cloud nine is the name Buckminster Fuller gave to his proposed airborne habitats created from giant geodesic spheres, which might be made to levitate by slightly heating the air inside above the ambient temperature....
  
   is Buckminster Fuller's proposal for a Tensegrity Sphere of size a mile in radius which would be large enough so that it would float in the sky if heated by only one degree above ambient temperature - giving could be a habitats for mini cities of thousands of people in each "Cloud Nine".

Orbital structures

• Orbital ring
  Orbital ring
  An Orbital Ring is a concept for a space elevator that consists of a ring in low earth orbit that rotates at above orbital speed, that has fixed tethers hanging down to the ground.The structure is intended to be used for space launch....
  
   is an enclosed loop slightly larger than the circumference of the Earth so that it can maintain low earth orbit.
• The Bernal sphere
  Bernal sphere
  A Bernal sphere is a type of space habitat intended as a long-term home for permanent residents, first proposed in 1929 by John Desmond Bernal....
  
   is a proposal for a space colony with a maximum diameter of 1.6 kilometers.
• The Stanford torus
  Stanford torus
  The Stanford torus is a proposed design for a space habitat capable of housing 10,000 to 140,000 permanent residents.The Stanford Torus was proposed during the 1975 NASA Summer Study, conducted at Stanford University, with the purpose of speculating on designs for future space colonies...
  
   is a different design with a diameter just under 1.7 kilometers.
• The O'Neill cylinder is yet another space colony proposal.

Trans-orbital structures

• A Skyhook
  Skyhook (structure)
  Skyhooks are a theoretical class of cable based techniques intended to lift payloads to high altitudes and speeds. The name skyhook is a reference to an imaginary hook that hangs from the sky....
  
   is a very tall structure that hangs down from orbit.
• A Space elevator
  Space elevator
  A space elevator, also known as a geostationary orbital tether or a beanstalk, is a proposed non-rocket spacelaunch structure...
  
   is a skyhook that is fixed to the ground
• A Space fountain
  Space fountain
  A space fountain is a proposed form of space elevator that does not require the structure to be in geostationary orbit, and does not rely on tensile strength for support. In contrast to the original space elevator design , a space fountain is a tremendously tall tower extending up from the ground...
  
   is held up by the momentum of masses which are shot up to the top at high speeds from the ground.
• A Lofstrom loop ("Launch loop") is a 2000 km long iron loop that projects up in an arc to 80 km that is ridden by maglev cars while achieving orbital velocity.
• StarTram Generation 2
  StarTram
  StarTram is a proposal for a maglev space launch system. The initial Generation 1 facility would be cargo only, launching from a mountain peak at 3 km to 7 km altitude with an evacuated tube staying at local surface level, raising ≈150,000 tons to orbit annually...
  
   is a maglev launch track extending from the ground to above 96% of the atmosphere's mass, supported by magnetic levitation.
• Rotovator proposals call for a large tether to transfer momentum between spacecraft in transit.

Stellar scale

• The Dyson shell (including its variation, the ringworld) has appeared in many works of fiction, including the Star Trek
  Star Trek
  Star Trek is an American science fiction entertainment franchise created by Gene Roddenberry. The core of Star Trek is its six television series: The Original Series, The Animated Series, The Next Generation, Deep Space Nine, Voyager, and Enterprise...
  
  universe.
• Larry Niven
  Larry Niven
  Laurence van Cott Niven / ˈlæri ˈnɪvən/ is an American science fiction author. His best-known work is Ringworld , which received Hugo, Locus, Ditmar, and Nebula awards. His work is primarily hard science fiction, using big science concepts and theoretical physics...
  
  's series of novels beginning with Ringworld
  Ringworld
  Ringworld is a Hugo, Nebula, and Locus award-winning 1970 science fiction novel by Larry Niven, set in his Known Space universe and considered a classic of science fiction literature. It is followed by three sequels, and preceded by four prequels, and ties into numerous other books set in Known Space...
  
  centered around, and originated the concept of a ringworld, or Niven ring. A ringworld is an artificial ring with a radius roughly equal to the radius of the Earth's orbit (1 AU
  Astronomical unit
  An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
  
  ). A star is present in the center and the ring spins to create g-force
  G-force
  The g-force associated with an object is its acceleration relative to free-fall. This acceleration experienced by an object is due to the vector sum of non-gravitational forces acting on an object free to move. The accelerations that are not produced by gravity are termed proper accelerations, and...
  
  s, with inner walls to hold in the atmosphere. The structure is unstable, and required the author to include workarounds in subsequent novels set on it.
• In the manga
  Manga
  Manga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...
  
   Blame!
  Blame!
  , pronounced "blam", is a ten-volume 1998 cyberpunk manga by Tsutomu Nihei published by Kodansha. A six part original net animation was produced in 2003, with a seventh episode included on the DVD release.- Plot :...
  
  the Megastructure is a vast and chaotic complex of metal, concrete, stone, etc., that covers the Earth and assimilates the Moon.
• In White Light by William Barton
  William Barton (writer)
  William Renald Barton III is an American science fiction writer. In addition to his standalone novels, he is also known for collaborations with Michael Capobianco...
  
   and Michael Capobianco
  Michael Capobianco
  Michael Victor Capobianco is an American science fiction writer.He is known for writing novels in collaboration with William Barton. Many of their novels deal with themes such as the Cold War, space travel, and space opera....
  
  , a Topopolis
  Topopolis
  A topopolis is a tube-like space habitat, rotating to produce gravity on the inner surface, which is extended into a loop around the local star. Topopoli can be looped several times around the local star, in a geometric figure known as a torus knot. The concept was invented by Pat Gunkel and...
  
   is presented as taking over the entire universe.
• In the Heechee
  Heechee
  The Heechee are a fictional alien race from the science fiction works of Frederik Pohl. The Heechee are portrayed as an exceedingly advanced star-travelling race that explored Earth's solar system millennia ago and then disappeared without a trace before humankind began space exploration.The...
  
   books by Frederik Pohl
  Frederik Pohl
  Frederik George Pohl, Jr. is an American science fiction writer, editor and fan, with a career spanning over seventy years — from his first published work, "Elegy to a Dead Planet: Luna" , to his most recent novel, All the Lives He Led .He won the National Book Award in 1980 for his novel Jem...
  
   the race of pure energy beings called The Foe have constructed the Kugelblitz, a black hole made of energy and not matter.
• In the Xeelee series
  Xeelee Sequence
  The Xeelee Sequence is a series of novels and short stories by British science fiction author Stephen Baxter. The novels span several billions of years, describing the future expansion of Mankind, its war with its arch-nemesis , and the Xeelee's own war with dark matter entities called photino birds...
  
   of books by Stephen Baxter
  Stephen Baxter
  Stephen Baxter is a prolific British hard science fiction author. He has degrees in mathematics and engineering.- Writing style :...
  
  , the eponymous alien race constructed the Ring, a megastructure made of cosmic string
  Cosmic string
  Cosmic strings are hypothetical 1-dimensional topological defects which may have formed during a symmetry breaking phase transition in the early universe when the topology of the vacuum manifold associated to this symmetry breaking is not simply connected. It is expected that at least one string...
  
  s, spanning over 10 million light years.
• The Ark from the Halo
  Halo (series)
  Halo is a multi-million dollar science fiction video game franchise created by Bungie and now managed by 343 Industries and owned by Microsoft Studios. The series centers on an interstellar war between humanity and a theocratic alliance of aliens known as the Covenant...
  
  universe which served as the last place of safety for the Forerunners from the flood, with the ability to rebuild destroyed Halos. Also in the games, orbital elevators on earth and other colonies are seen and mentioned.
• In Freelancer
  Freelancer (video game)
  Freelancer is a space trading and combat simulation video game developed by Digital Anvil and published by Microsoft Game Studios. The game was initially announced by Chris Roberts in 1999, and following many production schedule mishaps and a buyout of Digital Anvil by Microsoft, it was eventually...
  
  , The Dom'Kavosh's Dyson shell that is inhabited by a drone race created by the Dom'Kavosh, Nomads. This is reached via a hyper gate, created by the same creators as the Dyson sphere.
• The Saga of Cuckoo
  Saga of Cuckoo
  Saga of Cuckoo is a series of science fiction novels by Frederik Pohl and Jack Williamson. It consists of two novels:*Farthest Star *Wall Around A Star -Themes:...
  
   series novel Wall Around A Star
  Wall Around A Star
  Wall Around A Star is the second book of the Saga of Cuckoo series, the first of which was Farthest Star. The author is Frederik Pohl, in collaboration with Jack Williamson. The cover art for the 1983 edition was done by David Mattingly...
  
  mentions a proposal to build a super dyson sphere, completely enclosing the Galactic Center
  Galactic Center
  The Galactic Center is the rotational center of the Milky Way galaxy. It is located at a distance of 8.33±0.35 kpc from the Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest...
  
  .

Planetary scale

• Death Star
  Death Star
  The Death Star is a fictional moon-sized space station and superweapon appearing in the Star Wars movies and expanded universe. It is capable of destroying a planet with a single destructive super charged energy beam.-Origin and design:...
  
   from Star Wars
  Star Wars
  Star Wars is an American epic space opera film series created by George Lucas. The first film in the series was originally released on May 25, 1977, under the title Star Wars, by 20th Century Fox, and became a worldwide pop culture phenomenon, followed by two sequels, released at three-year...
  
  
• Borg Transwarp Hub and Unicomplexes, Federation
  United Federation of Planets
  The United Federation of Planets, also known as "The Federation" is a fictional interplanetary federal republic depicted in the Star Trek television series and motion pictures...
  
   Starbases and Fleet Yards
• Buster Machine III
  Buster Machine III
  Buster Machine III Buster Machine III Buster Machine III (バスターマシン三号）, also known as the Black Hole Bomb（ブラックホール爆弾）, is a superweapon of megastructure scale that appears in the science fiction anime OVA Aim for the Top! Gunbuster.-Description:...
  
   from Gunbuster
  Gunbuster
  Gunbuster, known in Japan as is a six episode anime OVA series created by Gainax in 1988. It was the directorial debut of Hideaki Anno, best known as the director of Neon Genesis Evangelion. The title is a combination of the titles of classic tennis anime Aim for the Ace!, whose plot inspired...
  
  .
• Culture Orbital
• Trantor
  Trantor
  Trantor is a fictional planet in Isaac Asimov's Foundation Series and Empire Series of science fiction novels.Trantor was first described in a short story by Asimov appearing in Early Asimov Volume 1. Later Trantor gained prominence when the 1940s Foundation Series first appeared in print . Asimov...
  
  , the capital of an interstellar empire in Isaac Asimov
  Isaac Asimov
  Isaac Asimov was an American author and professor of biochemistry at Boston University, best known for his works of science fiction and for his popular science books. Asimov was one of the most prolific writers of all time, having written or edited more than 500 books and an estimated 90,000...
  
  's Foundation series, is a planet entirely covered in one huge metal clad building, with only one small green space: the Emperor's palace grounds
• Coruscant, capital city in the Star Wars
  Star Wars
  Star Wars is an American epic space opera film series created by George Lucas. The first film in the series was originally released on May 25, 1977, under the title Star Wars, by 20th Century Fox, and became a worldwide pop culture phenomenon, followed by two sequels, released at three-year...
  
  universe, entirely covers its host planet. It serves as capital of first the Republic and then later the First Galactic Empire.
• The Galaxy Gun from the Star Wars
  Star Wars
  Star Wars is an American epic space opera film series created by George Lucas. The first film in the series was originally released on May 25, 1977, under the title Star Wars, by 20th Century Fox, and became a worldwide pop culture phenomenon, followed by two sequels, released at three-year...
  
  universe, a large space station
  Space station
  A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...
  
   designed to destroy entire planets from across the galaxy could be considered a megastructure because it's size is more than seven kilometers long.
• The Ori
  Ori (Stargate)
  The Ori are fictional characters in the science fiction television series, Stargate SG-1. They are a group of "ascended" beings who use their advanced technology and knowledge of the universe to attempt to trick non-ascended humans into worshipping them as gods.They first appeared in the ninth...
  
   Supergate seen in a number of episodes of Stargate SG1 could be classed as a megastructure
• In The Hitchhiker's Guide to the Galaxy
  The Hitchhiker's Guide to the Galaxy
  The Hitchhiker's Guide to the Galaxy is a science fiction comedy series created by Douglas Adams. Originally a radio comedy broadcast on BBC Radio 4 in 1978, it was later adapted to other formats, and over several years it gradually became an international multi-media phenomenon...
  
  series, Earth, as well as other planets, were artificial megastructures. Earth was intended to function as a gigantic computer, and was built by a race of beings who made their living by manufacturing other planets.
• The Star Forge from Knights of the Old Republic
  Knights of the Old Republic
  There have been a number of Knights of the Old Republic products.* Tales of the Jedi: Knights of the Old Republic, a 1990s comic book miniseries* Star Wars: Knights of the Old Republic, a role playing Star Wars video game released in 2003...
  
  
• Despite being sentient, the Transformers universes
  Transformer
  A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
  
   Unicron
  Unicron
  Unicron is a fictional character from the Transformers universe and toyline. Created by Floro Dery, he was introduced in the 1986 animated film The Transformers: The Movie as the film's main antagonist. Unicron is a prodigiously large robot whose scale reaches planetary proportions, and he is also...
  
  's 'metal planet' form is comparable to a megastructure.
• Mata-Nui in the BIONICLE
  Bionicle
  Bionicle is a line of toys by the LEGO Group marketed primarily for 5- to 16-year-olds. The line was launched on December 30, 2000 in Europe and June/July 2001 in Canada and the United States. "Bionicle" is a portmanteau constructed from the words "biological" and "chronicle"...
  
   franchise is classifiable as a megastructre. In the story he is a massive robot as tall as a planet, and inside his body, every inhabitant of the BIONICLE Universe (Matoran, Toa
  Toa
  Toa is a Polynesian word for warrior.Toa may also refer to:*Tindale-Oliver & Associates, Inc., a planning and engineering firm located in Florida*Toa River, a river in Cuba...
  
  , etc.) all live, unaware that they live inside a massive, space-traveling entity.
• Cybertron itself is a megastructure, comparable to Trantor or Coruscant on a smaller scale.
• The seven Halos
  Halo (megastructure)
  Halos are fictional megastructures and superweapons in the Halo video game series. They are referred to as "Installations" by their AI monitors, and are collectively referred to as "the Array" by the installations' creators, the Forerunners...
  
   from the Halo
  Halo (series)
  Halo is a multi-million dollar science fiction video game franchise created by Bungie and now managed by 343 Industries and owned by Microsoft Studios. The series centers on an interstellar war between humanity and a theocratic alliance of aliens known as the Covenant...
  
  universe are 10,000 km wide rings.
• Also from the Halo
  Halo (series)
  Halo is a multi-million dollar science fiction video game franchise created by Bungie and now managed by 343 Industries and owned by Microsoft Studios. The series centers on an interstellar war between humanity and a theocratic alliance of aliens known as the Covenant...
  
  universe, the Ark is a 127,530 km diameter structure from which the Halo Array can be activated.
• In the Robotech
  Robotech
  Robotech is an 85-episode science fiction anime adaptation produced by Harmony Gold USA in association with Tatsunoko Production Co., Ltd. and first released in the United States in 1985...
  
   Sentinels novels, Haydon IV is an artificially constructed cyber-planet with android citizens.
• In the Invader Zim
  Invader Zim
  Invader Zim is an American animated television series created by Jhonen Vasquez. It was produced by and subsequently aired on Nickelodeon. The series revolves around an extraterrestrial named Zim from the planet Irk, and his ongoing mission to conquer and destroy Earth...
  
   episode "Planet Jackers", two aliens surround the Earth with a fake sky in order to throw it into their sun.
• Nightmare's fortress from Kirby: Right Back at Ya!
  Kirby: Right Back at Ya!
  Kirby: of the stars, known in Japan Kirby right back at ya!', is an anime series based on Nintendo's Kirby franchise. The series was produced by Warpstar Inc., a company formed between a joint investment between Nintendo and HAL Laboratory, Inc.The series, which takes place in a village called...
  
   can be classified as a megastructure because it's the size of a small planet.
• In several works, Arthur C. Clarke writes about a colossal hollow tube
  Rama (spacecraft)
  Rama is a fictional mysterious extraterrestrial vessel that is the subject and setting of the science fiction novel Rendezvous with Rama by Arthur C. Clarke, and the later sequel trilogy by Clarke and Gentry Lee: Rama II, Garden of Rama, and Rama Revealed. It exists in a fictional future timeline...
  
  , first described in "Rendezvous with Rama
  Rendezvous with Rama
  Rendezvous with Rama is a novel by Arthur C. Clarke first published in 1972. Set in the 22nd century, the story involves a cylindrical alien starship that enters Earth's solar system...
  
  " (1973), and inhabited by different races.
• Onyx in the Halo universe is essentially a planet made entirely out of forerunner sentinels.
• High Charity, the Covenant's mobile planetoid station, in the Halo
  Halo
  Halo may refer to:* Halo , a glow or ring of light around a head or person in art-Game franchise and spin-offs:*Halo , a video game franchise by Bungie and Microsoft Game Studios...
  
   universe.
• The Citadel in the Mass Effect
  Mass Effect (series)
  Mass Effect is an award-winning, bestselling series of science fiction RPG third-person shooter video games developed by the Canadian company BioWare and released for the Xbox 360, Microsoft Windows and, from the second installment, for the PlayStation 3...
  
   universe is an enormous space station constructed by an ancient race of mechaines called the Reapers billions of years before the games in the series. At the time of Mass Effect 2, it's population is 13.2 million.
• In the game Airforce Delta Strike
  Airforce Delta Strike
  Airforce Delta Strike, known as Airforce Delta: Blue Wing Knights in Japan and Deadly Skies III in Europe, is the third installment in the Konami Airforce Delta series. It was released in 2004 exclusively on the PlayStation 2...
  
  a large Space Elevator called the Chiron Lift is used to send supplies out into outer space.

Megascale structures

Structures that might not be classified as "Megastructures" because they do not meet the requirements, but are indeed "Mega" sized structures/constructions.

Stellar scale

• Dyson Bubble - Collection of separate constructions.
• Dyson Swarm - Collection of separate constructions.

External links

• National Geographic Channel
• Megastructure.org Megastructure Art.