To the ancient Greeks, the underworld was believed to be underground. Many caves throughout Grecian empire were thought to have deep fissures inside of them that led to the underworld. One of the most famous of these caves, Diros, is located in Sparta.

The Greek underworld, known as Hades and ruled over by the god Hades, had several rivers in and around it, but the more well known five rivers are Styx, Acheron, Pyriphlegethon, Cocytus and Lethe. There is come conflict as to which river Charon ferried the newly deceased souls across. The river Styx (the river of Hate), which circled the underworld nine times, was considered the boundary between the living world and the underworld and some believe this to be the river that the newly dead souls must cross to enter the underworld. The river Acheron (the river of Woe), is a branch of the river Styx and some believe it to be the one that the newly deceased must cross to enter Hades. The river Pyriphlegethon (the river of Fire), also surrounded Tartarus and the entire underworld, running parallel to the river Styx. The river Cocytus (the river of Wailing), and flows into the river Acheron. The river Lethe (the river of Forgetfulness), from which souls would drink to forget their former lives before being reincarnated. It is believed by some that all the rivers merged together in the Stygian marsh or the Acherusian Lake.

When people died in ancient Greece, they would be buried with a coin on their lips to be used as a payment for crossing into Hades. Hermes, the son of Zeus, would escort the newly deceased soul to the river Acheron. Once there, the soul would pay the fare to the ferryman, Charon, in order to cross the river to the entrance of Hades. If the soul did not have the fare to pay Charon they would be left to wonder between the world of the living and the underworld on the outmost region of the underworld.

Once the soul had crossed the river it would pass through the gate into Hades. This gate was guarded by Cerberus, the three headed dog, who would allow soul to pass into Hades, but would not let any soul leave. Once the soul has entered Hades, they would be judged by three judges, Aeacus, Minos, and Rhadamanthus. These formerly mortal judges would consider the actions that each soul performed while they were alive and then the judges would determine which of the shadowy regions of Hades that that particular soul would spend eternity. It was commonly believed by the ancient Greeks that the dead were able to eat, drink and could feel emotions so it was important to know where a soul would spend eternity.

For those who led honorable lives, they would take the right-hand fork in the path through Hades, which led to the Elysian Fields. The Elysian Fields (Elysium) were a pleasant place with its own sun, stars and meadows. All of the souls in Elysium drink from the river Lethe to forget their former life. Some souls are destined to be reincarnated and this is why they are required to drink from the river Lethe in order to forget their former life.

For those souls who had committed terrible crimes during their life, they would be forced to take the left-hand fork in the path through Hades, which led to Tartarus. Tartarus was a place of eternal punishment. Tartarus is believed to be the realm of Erebus, who is said to be pure Darkness. There the wicked soul would remain for all eternity, sentenced to roll huge rocks, whirl around for eternity or sit in the chair of oblivion.

For those souls who had wronged others while alive, but are believed to be redeemable, are put in Tartarus, but after a time the rivers of Cocytus or Pyriphlegethon might wash them into the Acherusian Lake where they can beg for forgiveness for their wrongs from the people they have wronged. If they are not forgiven, they are cast back into Tartarus to start all over again until they are forgiven and they are allowed out of Tartarus and they are not punished further.

Although many of the beliefs of modern religion are very similar to the mythology of the Greek underworld, for the ancient Greeks, the underworld wasn’t really as terrible as the Christian Hell, it was more like a bad dream in which the shadowy dead souls faded away until they were nothing.