The Depths of Eternity was at the bottom of the Lake of Apparitions. A lake found "Beyond shadows", the place Force sensitives go when they detach their Force presences from their physical beings. When walking across the lake one had to stay on the path or they would fall into the Depths of Eternity. If they fell in they could not be saved or retrieved.
When Luke and Ben Skywalker went to Sinkhole Station in the Maw they met the Mind Walkers who took them "Beyond shadows". While crossing the Lake of Apparitions Luke stumbled causing his whole leg to go underwater. When Ben looked to see the cause, he saw his father had stumbled at the sight of the Force ghost of Ben's mother floating on the surface.
- Abyss (First appearance)