In an environment where hundred-meter waves and radiation storms are relatively common events, some are forced to accept temporary or even mobile settlements. The rest choose to build big and to last, and they inhabit Arcatia’s supercities. Supercities are characterized by exceptional population density and a massive scale of construction focused around single buildings as self-contained environments and the city as a whole distinct and protected from the surrounding environment.
Unity supercities are the perfect embodiment of these ideas, taking the form of massive tetragonal pyramid arcologies rising a half mile or more into the sky. The interior provides a much greater area of usable infrastructure than a collection of conventional structures ever could, featuring vast gardens, interior lakes, and of course endless tracts of business, living, and recreation space. The centrally planned and intimately controlled nature of Unity planning means many such supercities are largely empty or even home to vast unfinished sections, projects outlined for some predicted increase in population or possible structural requirement. The Unity also has the land and tectonic architecture for smaller, more conventional cities, though these tend towards inland areas rarely visited by outsiders and largely important only to internal commerce and affairs.
Serican and Rastakgic supercities share a more conventional layout, featuring a number of vast towers whose monolithic foundations form the outlines of a sort of ‘undercity’ that thrives below the darting aircraft and weaving maglev trains of the city proper. Some of these buildings stretch over a mile high, requiring massive interlinked foundations whose main reinforcing layers protrude dozens of stories aboveground. Barrier Walls encircling such cities are common, forming a natural boundary to the undercity, keeping the foundations safe from particularly devastating waves, and providing the backdrop upon which refugee-filled shantytowns inevitably grow in times of crisis. Since landlocked cities are extremely rare, harbor districts are usually protected by their own layers of interior and exterior walls and shock-absorbing infrastructure, keeping them secure from natural and human-borne calamities alike.
Protectorate cities tend towards a hybrid between the Unity and Serican standard, featuring single massive sealed structures with a number of external ‘buds’ and later additions, inevitably leading to other independent structures trailing away from the original arcology (usually in the shape of a three-winged hall or spire). Protectorate arcologies tend to feature external harbors and extensive atmospheric manipulation infrastructure dotting the exterior as opposed to the all-encompassing nature of their Unity counterparts.
Pax and Jahangi Supercities are, well, largely nonexistent. In addition to a preference for conventional rural life (which would be utterly impossible in Serica) the diverse nature of different internal groups and potential for conflict (Jah) or tiny population and danger of flooding (Vilum) make Supercities generally less attractive. Even so, the Equilibrium has no shortage of great settlements or impressive architecture, and the floating Jahangi ‘trade cities’ are a type of supercity all their own.