LatinAvernus, from Ancient Greek αορνος (aornos), αϝορνος (awornos, “birdless”), from ἀ- (a-, “without”) + ὄρνις (ornis, “bird”). The lack of birds was likely due to fatal gases like carbon dioxide seeping from the volcanically active lake.
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The lakes Averno (Avernus), Lucrino (Lucrinus), Fusaro (Palus Acherusia), and Agnano are within this group, which has shown activity in historical times.
The lake of Avernus, as an entrance to the infernal regions, was sacred to her.
AVERNUS, a lake of Campania, Italy, about II m.
64) seem to have begun near Lake Avernus; indeed, according to one theory, the Grotta della Pace would be a portion of this canal.
Nero's scheme for the construction of a canal from Lake Avernus to Ostia would have restored the balance in its favour (though it certainly could not have been continuous all the way to Rome with the means of engineering then available).