Acheron

The Acheron river was a mythical stream (or sometimes a lake) in ancient Greek mythology, though it is also occasionally associated with the real Epirus river, which flows underground in part of its passage. Acheron translates as "river of woe" and, contrary to popular belief, is also the river that Charon ferried the newly dead souls across into Hades.

The word is also occasionally used as a metaphor for Hades itself.

The god of the river, an Oceanid and son of Oceanus and Tethys, fathered Ascalaphus with Orphne.

Virgil VI, 107