A seemingly boundless city, hundreds or thousands of kilometres across. Central citizens rarely see the outside, and newcomers take weeks of travel to get to the centre.
Many years ago it acquired the name Exapolis because of its size, but locals believe this name comes from "Exalted City", as the town is favoured by an overarching deity known only as the Divine. Townspeople focus their day-to-day behaviour in order to channel the holy power of the Divine, often by performing generous acts towards other Exapolitans or recruiting new converts.
In the air over the thickest part of the town hangs an inky black layer that blots out all the sunlight: the Veil. Few know where it came from, most citizens believe the Divine wanted to limit the hubris of Exapolis' expansion. To pierce the thin Veil and harvest sunlight, the centre of town has buildings of up to one kilometre in height, built entirely out of blue cobalt.
The centre of town is therefore in a state of permanent night, illuminated by golden veins of radium oil, condensed from the sunlight collected above. As one makes their way out of town the veil gets thinner, the radium oil less common, and the cobalt a dull copper colour - traditional construction materials (wood, bricks, stone) are used where the Veil is not visible.