Agartha
Agartha is both the name of the capital city and the kingdom that dominates the subterranean cavern network known as Hollow Earth. Once said to be the birthplace of dragons, Agartha remains a stronghold for the great flying beasts to visit, though it is now ruled by the local humanoids such as dolkalfar, duergar, molemen, morlocks, myrmidons, svirfneblins, wurms, popobawas, and similar denizens of the dark.
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