In the north-east of Campania Felix, separated from the Campania Apennines by the valley of the Medio Volturno, the massif of the Trebulani Mountains rises, also known as the Colli Caprensi.

Mount Massico with its 813 meters is the highest relief of the mountain range which starts from the slopes of the Roccamonfina volcano and reaches the Tyrrhenian Sea.

On its shores violets grew, and this is why the Greeks called it Clanis. The River Clanis rises on Mounts Tifatini.

It starts in the area of Frosinone from the confluence between the Liri, which first crosses Abruzzo and Lazio, and the Gari, which rises at Cassino and is often called Liri-Garigliano.

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

Older than Vesuvius. It is among the biggest of Italy, but extinct since fifty thousand years ago. The Roccamonfina volcano rises isolated between the Aurunci Mountains, in Lazio, and in Campania Felix the plain of Garigliano and the Massico massif, separating it from the Tyrrhenian Sea.