Khordaldrum
Khordaldrum was a dwarven stronghold before the Dragon Wars but was abandoned at some point during the war. The ruins of Khordaldrum have recently been rediscovered by an elven-led exploration under the Wellbarrow southern light house.
The stronghold was made for an unknown purpose but held room for a large number of dwarves, considering the storage facilities and kitchen size.
During the evacuation of the stronghold, a curse was laid upon it, preventing dragons from entering, and it had a nasty effect on other creatures with dragon blood who entered. Some sort of illness spread, turning lizard-blooded kobolds into walking undead creatures, infecting other inhabitants entering the stronghold in the past few hundred years, including at least humans, troglodrakes and bugbears.
Much of the ruins are cut off by cave-ins and require further exploration.