Lake Avernus

Lake Avernus is a small, perfectly circular volcanic lake about 4 kilometres west of central Pozzuoli, occupying an ancient crater in the Campi Flegrei. The lake is strikingly beautiful — deep blue-green water surrounded by wooded slopes — and the contrast between its peaceful appearance and its ancient reputation as the gateway to hell is part of its appeal. A walking path circles the lake, taking about an hour at an easy pace.

Near the shore, you can find the remains of what the Romans called the Cave of the Sibyl of Cumae — a long, arched tunnel carved into the volcanic tufa that was associated with oracular tradition. The actual Cave of the Sibyl is at Cumae, several kilometres away, but the atmosphere of tunnels and steam vents around the lake fed the mythology. The ancient tunnel near the lake, sometimes called the Grotta di Cocceio, runs all the way through the hill toward Cumae, though it is not always accessible.

things to do sight
A story
Virgil set the entrance to the underworld at Lake Avernus in the Aeneid: "easy is the descent to Avernus; the door of black Dis stands open night and day." The lake was thought to emit toxic gases that killed birds flying over it — Avernus comes from the Greek for "birdless" — a belief that may have had some basis in the actual carbon dioxide seeping from the volcanic ground. Agrippa dredged and connected it to the sea in 27 BC to create the Portus Julius naval base, largely destroying its infernal atmosphere.