Limbo

Limbo, sometimes called the Island of the Lost, is an island deep within the fogs of the Astral Sea, and nestled in the center of the Celestial Plane in an area of planar overlap. It is of infinite size, yet has shoreline all the way around, and you can travel from one side to the other in a relatively short amount of time. It is the holding place for the souls of the dead before they are weighed on the Scales Link, and shipped off to their deity's demiplane. New souls appear every second as angels carry them up from the Ethereal Plane.