Cocytus

Cocytus /koʊˈsaɪtəs/ or Kokytos /koʊˈkaɪtəs/ (Ancient Greek: Κωκυτός, literally "lamentation") is a river in the underworld in Greek mythology. Cocytus flows into the river Acheron, on the other side of which lies Hades, The Underworld, the mythological abode of the dead. There are five rivers encircling Hades. The River Styx is perhaps the most famous; the other rivers are Phlegethon, Lethe, Acheron and Cocytus.

The Cocytus river was one of the rivers that surrounded Hades. Cocytus, along with the other rivers related to the underworld, was a common topic for ancient authors. Of the ancient authors, Cocytus was mentioned by Virgil, Homer, Cicero, Aeschylus, Apuleius and Plato, among others.

Cocytus also makes an appearance in John Milton's epic poem Paradise Lost. In Book Two, Milton speaks of "Cocytus, named of lamentation loud / Heard on the rueful stream".

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