The Well of Souls was the name given to a location on an unnamed planet by its pre-Hebitian natives. The site, located under the Red Mountains, was apparently a prison for a number of non-corporeal lifeforms, who became known as dithparu, or Night Spirits. Upon death, the royal rulers of this world were brought down to the Well of Souls, accompanied by their eldest sons. There, a dithparu would possess the son, as another who had formerly possessed the monarch returned to the Well.
The Well of Souls was abandoned when a new king, Nartal, fled before the dithparu could join with him. As a result, the machinery that supported the planet went untended and failed, and the humanoid population apparently died out. It was rediscovered in 2336 by two young explorers, Jason Garrett and Pahl. It was sealed off again by Garrett's father, Ven Kaldarren. (TLE novel: Well of Souls)