‘”But when in thy ship thou hast now crossed the stream of Oceanus, where is a level shore and the groves of Persephone – tall poplars, and willows that shed their fruit—there do thou beach thy ship by the deep eddying Oceanus, but go thyself to the dank house of Hades. There into Acheron flow Periphlegethon and Cocytus, which is a branch of the water of the Styx; and there is a rock, and the meeting place of the two roaring rivers.” Odyssey 10.506ff. (online text: Eng., Grk.)
Book 11 of the Odyssey seems to describe a necromancy (the summoning of shades of the dead) that evolves into a catabasis (a heroic journey to the underworld by a mortal, featured in myth of Heracles and Theseus). There were four major locations (among many) for an oracle of the dead (nekuomanteion): the River Acheron in Thesprotia, west Greece; Lake Avernus (Lago d’Averno) near Naples; Cape Tainaron (or Matapas/ Matapan); and Heraclea Pontica (Karadeniz Eregil), a Greek colony on the south coast of the Black Sea. The first two are most relevant to localization of the journey of Odysseus. Arguably the Homeric underworld episode attests to the localization of the underworld (or rather oracle/entrance) in Thesprotia; Greek colonists then transferred the localization to Lake Avernus (so Ogden 2001:xxiv-xxv, 43, 61-62, convincingly).
The localization of the “Cimmerians” who live near the Odyssey’s underworld is a further complication (Gimmerians/Cimmerians were a historical nomadic people associated with the Black Sea area and Asia Minor). The same is true for Homeric underworld topography such as Leukas (“White”) Rock, though it would seem somehow linked to Thesprotia, for a northern Ionian island with famous cliffs is named Leukas (Lefkas).
Lake Avernus eventually became associated with the catabasis of Aeneas. Lost plays of Sophocles and Aeschylus may have localized Odysseus’ underworld at Avernus. Other Greek sources localized the Homeric underworld at Avernus; including the 4th c. Ephorus certainly did in his lost history. Cape Tainaron was sometimes said to be the place where Heracles brought Cerberus up from Hades (see Fermor 1958:129-32 for a different, modern localization of the underworld in this area; Fermor also briefly discusses other mythological entrances, like Thesprotian Acheron, Avernus, and Enna). Enna, Sicily featured a temple dedicated to Demeter, whose daughter Persephone was sometimes thought to have been abducted by Hades in the nearby plains, particularly by Lake Pergusa, though he enters the underworld through the pool of Cyane near Siracuse.
Pausanias, Description of Greece 1.17.4
Strabo, Geography 5.4.5
Pliny, Natural History 3.9
Dio Cassius, Roman History 48.50.4
Cicero, Against Verres 2.4.107
Ovid, Metamorphoses 5.462ff.
Pausanias, Description of Greece 3.25.5
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