Interterranean Arcology

On Evermorn, developable land is at a premium. The planet is almost 85% water by surface area and, in the interest of both agriculture and ecocultural preservation, around three-quarters of what remains is taken up with farms, forests, preserves, and rural hamlets. Without the ability to expand into a sprawl, Evermornan cities have expanded vertically instead of horizontally. Above-ground expansion, however, often comes into conflict with the uniquely durability-oriented design ethos of Evermornan construction; a long history of wars with the totalitarian Cinnabar Hegemony and iconoclastic Obsidian Republic have turned the minds of Evermornan civil engineers to questions of defense, redundancy, and paranoia about weapons of mass destruction. It is in this context that the notion of an 'interterranean arcology' came to the forefront of Evermornan planetary structure design, and it is a concept which still resonates with Evermornan colonists in the asteroid field, Armoa, and beyond.

Between Crust & Sky

An interterranean arcology appears to be a normal (if abnormally robust) skyscraper on the surface, with an outer (often obelisk-, pyramid-, or dome-shaped) shell of tinted and field-proofed glass encasing a similarly-shaped inner structure of steel and pre-stressed concrete. Often, the space between inner and outer shells features tiers of green space, including trees and gardens, and sometimes the shell features algae channels in lieu of tinting to turn excess sunlight into food and fresh air.
On the walkways leading between the shell and the main structure itself, however, one might look down only to see trenches up to a mile deep. These display the true nature of the arcology as a structure that, for all its height above ground, is much more massive beneath it - much in the manner of the many icebergs that constantly roam the small world's chilly seas. Indeed, many interterranean arcologies, if measured from the fusion cores and waste processing facilities in the basement to the highest crests of the protective shells, are more than a mile tall - and, if measured across all the cathedral-huge underground public squares, often double or more that width. Seaside interterranean arcologies may feature outer shells and observation decks which extend along the continental shelf as deep as the upper boudaries of the bathypelagic zone.
One notable similarity across all interterranean arcologies is the presence of a 'city square': a massive central shaft where the light of the midday sun can directly percolate into the deepest points of the arcology. Roads, walkways, and parks are suspended around and across this central square to permit the residents of the arcology to enjoy a close approximation of nature. Sometimes, the outer shell of the arcology may feature a louvred 'capstone,' allowing rain or other seasonal weather to come in while still being subject to control if it becomes too intense. Other times, pseudo-weather may be generated, in the form of clouds or even rain, from the precipitation of water from the air on the uppermost reaches of the structure, and this, too, may be controlled through various systems. Arcology weather is somewhat influenced by depth, with temperature rising the deeper one goes; this temperature gradient can be used with thermocouples to generate auxiliary power, with output peaking during surface winters.

Construction

The invention of the auto-factory, fusion power, advanced robotics, and advanced geological surveying tools have enabled Evermornans to extract mineral resources from the ground and immediately 're-print' them into useful constructions, greatly speeding the process of constructing underground vaults. Large spaces are excavated in the planetary crust in tandem with construction efforts above ground, which usually utilize the very stone and glass extracted from beneath the growing structure; even when building something new, the Evermornan ethos of efficient material usage and repurposing is visible.
Over time, these vaults are reinforced, routed with city utilities, connected to underground public accessways, and filled with multi-story residential, commercial, or industrial spaces. While these underground vault-burroughs are by no means luxurious, they are also not austere, with ample lighting and greenery provided and the upper reaches decorated or holographically projected upon to emulate skyscapes of all description. Each vault is said to feel something like it's own township or neighborhood; indeed, redundancies and access control infrastructure are installed such that, in the event of an emergency (such as surface bombardment), each vault can operate independently of the others for a time. Semi-domesticated wildlife, including augmented animals like crows, magpies, dogs, and (if waterside) cetaceans, are introduced into vaults to help maintain a semi-closed ecology as well as provide psycological comfort to the residents.

Type

Arcology / Residential Complex

Owning Organization

Cobalt Protectorate