Arcology

An arcology was a type of archeological structure. It was a large, environmentally-friendly habitat that could support one million residents.

History and specifics
In the 2260s, Pavel Chekov saw illusions of four such structures he recognized from Moscow while under the influence of the Vardan illusion machine, which was being controlled by a group of archeologists. 

In 2270 at the Web of Worlds, Chekov and Hikaru Sulu visited the Fiilestii biome module, a 1000-kilometer wide structure which simulated the original planetary home of the avian race. Kilometers-high arcology towers shaped like narrow cones rose from the ground, with several disc-shaped levels embedded along it. Each disc measured dozens of meters thick, hundreds of meters in radius, and contained residences and job sites for the Fiilestii.

In 2270 James T. Kirk and Nyota Uhura toured the Tessegri module of the Web of Worlds, which at a glance resembled New York City with a larger Central Park, except that each building was an arcology shaped like a ziggurat and was surrounded by huge parkland, which was amenable for the Tessegri, who loved to walk, jog or run everywhere. Despite their massive size, the design of the arcologies directed ample light to the ground. Interiors were also spacious and well lit. The roof of the largest arcology, kilometers high, provided a stunning view of the metropolis. 

In 2382, Breen Silwaan dissenter Deshinar Tibbonel brought Julian Bashir and Sarina Douglas to her home on the planet Salavat, an arcology in level 15 of the Breen settlement Rasiuk. The structure had multiple exits, with the main entrance hall wide enough to accommodate at least 50,000 people at once. Tibbonel hid the Starfleet officers within a crowd at shift change to prevent them from being identified or tracked. She lived on the 71st floor. 

Arcologies

 * Moscow (Russia, Earth)
 * Kalilingrad
 * Leningorá
 * Spirit of Tomorrow
 * Web of Worlds (Cherela)
 * Fiilestii module arcologies
 * Tessegri module arcologies
 * Salavat (Breen Confederacy)
 * Rasiuk Level 15 arcology
 * Rasiuk Level 15 arcology