From Encyclopedia Arelithica
Structure
In the Sewers there are a lot of pipes and places to release the unwanted of Cordor, there is water, stones, and bridges, although the current residents have cleaned up a bit, not that it makes a difference, they still are sewers after all
Population
The friendly residents of the sewers range from your typical rat, to trolls who must be blind since they're quite a ways away from home, in any case the sewers also make itself a home to friendly bandits and other who are much less lucky as they wouldn't be able to use their spoils even if they got some.