An elaborate system of levees protects this below-sea-level metropolis from its adjacent climate. Fully half of Sur'daro's structures are docks, warehouses, or other import-related structures, despite Sur'daro not being coastal; the city is built on a confluence of a number of rivers. Sur'daro's population is twice that of any other great city on Wanisin, and its streets and buildings are lavish. City floods are relatively common, on the order of once or twice per millennium. The ever-expanding fortifications around the city occasionally influence this rate, either diverting water in a way that reduces flooding risks, or damming waterways to make it worse.