The Western Borderlands
Caves of Chaos
The Caves of Chaos were formerly home to a large settlement of humanoids, including kobolds, goblins, orcs, hobgoblins, and gnolls. They had been organized in secret by a priest of chaos living within Ostrom Keep. In the process of driving monsters from the caves, a band of adventurers discovered the priest’s plot and slew him and his followers.
The caves have been abandoned since, although the Castellan ensures that they are patrolled periodically to prevent resettlement by monsters.