It rises at the foot of Mounts Trebulani, at 86 meters above sea level, in the territory of Calvi Risorta.

For the ancients, it was the river of the myth, which gave forgetfulness to whoever drunk its water.

The extinct volcano of Roccamonfina is the heart of the park that protects since 1993 a territory of great naturalistic value from Campania Felix up to the border with Lazio. Eleven thousand hectares of volcanic rocks and limestone, streams and lush vegetation, dotted with ancient hamlets keeping alive the imprint of their past and the heritage of their identities.

For the ancient Italic peoples it was a sacred river. On the shores, they erected sanctuaries such as the Demetra and Teano one.

It is one of the favourite stopping points in the long spring migration from Africa to Central Eastern Europe on the Tyrrhenian route.

It rises from Lake Matese and in the first part of its way, it is characterised by cascades and differences in heights.