Location from Percy Jackson by Rick Riordan
Hades' realm — where every soul goes after death. It has an entrance in Los Angeles, which explains a lot about LA.
The Underworld is where the dead end up — sorted into Elysium (heroes and the virtuous), the Fields of Asphodel (average souls who drift as grey shimmering ghosts), or the Fields of Punishment (the wicked, who suffer creative eternal torments). Charon ferries souls across the Styx for a golden drachma — no coin, no crossing. Cerberus guards the entrance with three heads and a weakness for rubber balls. It's organized like a massive bureaucracy, which is both terrifying and mundane. Percy has visited multiple times, which the dead find deeply confusing because living people are not supposed to be there.
A vast underground realm accessed through DOA Recording Studios in Los Angeles (Charon runs the elevator). Fields of Asphodel stretch endlessly — grey, flat, and populated by shimmering ghosts. Elysium glows golden in the distance. The Fields of Punishment are exactly what they sound like. Hades' palace sits on a hill overlooking it all.
Also known as: the Underworld, Hades' realm