Acheron, in classical mythology, one of the five rivers of Hades. The Acheron was tributary to the Cocytus, the Cocytus tributary to the Styx. The name Acheron means "River of Sorrows," or "River of Eternal Woe." In the later legends, Acheron was a son of Helios and Demeter, who gave drink to the Titans during their war with Zeus. For thus aiding the enemy, he was punished by being transformed into an infernal river. The name Acheron is used figuratively to designate the whole lower world. Milton speaks of the river in the second book of Paradise Lost as "Sad Acheron of sorrow, black and deep."
