Hades, according to various Christian denominations, is "the place or state of departed spirits", borrowing the name of Hades, the Greek god of the underworld. It is often associated with the Jewish concept of Sheol.
Lazarus and the Rich Man (illumination from the Codex Aureus of Echternach).
The underworld, also known as the netherworld or hell, is the supernatural world of the dead in various religious traditions and myths, located below the world of the living. Chthonic is the technical adjective for things of the underworld.
Yggdrasil, a modern attempt to reconstruct the Norse world tree which connects the heavens, the earth and the underworld
The legs of the god Vishnu as the Cosmic Man depict earth and the seven realms of the Hindu underworld of Patala. The feet rest on cosmic serpent Shesha.