Phlegethon

Phlegethon, also spelled Phlegethón, is the mythological river of fire in Greek tradition. It is traditionally listed among the five rivers of the Greek underworld—the others being Styx, Lethe, Acheron, and Cocytus. The name derives from the Greek phlégethón, meaning "fiery" or "burning." In most accounts, Phlegethon is a stream of flame that encircles or runs through the realm of the dead, sometimes surrounding Tartarus or serving as a barrier to the punishments of Hades.

In classical poetry and prose, Phlegethon functions as a vivid symbol of punitive fire. Its imagery reinforces the idea that the underworld contains fixed zones of suffering, with the river of flames associated particularly with the torments of the wicked. Dante's Inferno also popularized the idea of a fiery river in the hellish landscape; while Dante names no Greek river as Phlegethon, his depiction of boiling blood in the seventh circle echoes the ancient topos of a fiery stream as punishment. The river appears in later adaptations and literary allusions that rely on the old association between water and flame in the afterlife.

Beyond antiquity, Phlegethon is used in modern literature and scholarship as a toponym and symbol. It appears in fantasy settings as a fictional river or landscape and as a metaphor for destructive heat or unstoppable force. As a mythological term, it remains a standard reference in studies of Greek underworld geography and in translations that seek to convey the full sensory impact of ancient descriptions.