The Underdark is a network of subterranean caverns, known to span across the entire main continent on Aber-Toril. As a result, it was not always possible to travel from one end of the Underdark to the other. The term is used for the Forgotten Realms setting, with the concept arising in Greyhawk.
Races of the Underdark
The following is a list of some of the races that reside in the Underdark.