The New Student's Reference Work/Avernus

Aver′nus, called now Lago d’Averno, is a small circular lake in Italy. It is about a mile and a half around, and lies in the crater of an extinct volcano. It is in some places 200 feet deep, and is almost completely shut in by steep and wooded heights. The sulphurous vapors arising from it were believed in ancient times to kill the birds that flew over it, and so it probably got its name from a Greek word meaning “birdless.” Its gloomy and awful appearance made it the center of almost all the stories of the ancients about the world of shades. Here was Homer’s and Vergil’s entrance into the lower world, and here were the Elysian fields, the cave of Hecate and the grotto of the Cumæan Sibyl. Agrippa connected it with the Lucrine Lake and the sea, making it a sort of harbor; but the volcanic upheaval of Monte Nuovo, in 1358, again made Avernus an inland lake. On its east side are the ruins of a temple of Apollo, and on its south side what is shown as the grotto of the Sibyl.