The Underworld, is not entirely unlike Heaven/Hell, but it's not the same, either. The Underworld has the glorious area known as the Elysian Fields, which is similar to Heaven. Hades' realm also has the torturous area known as Tartarus, corresponding with Hell. It also allots special areas for various types of deaths, and contains the Plain of Asphodel, which is the joyless realm of ghosts. This last is the main area for the souls of the dead in the Underworld -- neither torturous nor pleasant, but worse than life.

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Greek underworld (often shortened as Underworld, depending on the context) is a general term used to describe the various realms of Greek mythology which were believed to lie beneath the earth or beyond the horizon.

This includes:

• The great pit of Tartarus, which was originally the exclusive prison of the old Titan gods, but which later came to mean the dungeon home of the damned souls
• The land of the dead ruled by the god Hades, which is variously called the house or domain of Hades (domos Aidaou), Hades, Erebus, the Asphodel Fields, Stygia and Acheron ;
• The Islands of the Blessed or Elysian Islands ruled by Cronus (According to Pindar - other accounts differ), where the great heroes of myth resided after death ;
• The Elysian Fields ruled by Rhadamanthys, where the virtuous dead and initiates in the ancient Mysteries were sent to dwell.

The five rivers of Hades are Acheron (the river of sorrow), Cocytus (the river of lamentation), Phlegethon (the river of fire), Lethe (the river of forgetfulness) and Styx (the river of hate), which forms the boundary between upper and lower worlds.

The ancient Greek concept of the underworld evolved considerably over time.

The Homeric underworld

Further information: Hades

The underworld is ruled by Hades. The oldest descriptions of the underworld can be found in Homer's Iliad and Odyssey.The other poets of old epic such as Hesiod describe it similarly. In the Odyssey the Underworld is located beyond the Western horizon. Odysseus reaches it by ship from Circe's island, and later on, the ghosts of the suitors are herded there by Hermes Psychopompus (the guide of the dead). He herds them through the hollows of the earth, beyond the earth-encircling river Oceanus and the gates of the (setting) Sun to their final resting place in Hades.

The Classical underworld

The Homeric Hymns and lyric poet Pindar introduce the paradise-like realm of Elysium where the virtuous dead were sent after death. This blessed afterlife was also promised in cult to the initiates of the ancient Mysteries.

Local cults

Many local cults in Greece claimed to possess entrances to the underworld, and had special religious rites associated with these. The most famous of these is perhaps a cave in Sparta, which was found to be nothing but an empty cave. Ancient travel writers and geographers such as Pausanias and Strabo describe these.

The Ferryman

The deceased entered the underworld by crossing the River Akheron or Styx ferried across by Charon (kair'-on), who charged an obolus, a small coin, as a fee. This coin was placed in the mouth of the deceased by relatives. Paupers and the friendless gathered forever on the near shore. The far side of the river was guarded by Cerberus, the three-headed guard dog of Hades.

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