The river Isclero (30 km) starts in the Caudina valley from the junction of several minor watercourses called “big valleys”.

The Sabato river (50 km) starts from the Colle Finestra on the Monte Terminio and flows for in Irpinia for most of its stream,

Il fiume Tammaro (78 km) nasce nel Molise non lontano dal confine con la Campania, in cui entra tra Sassinoro e Santa Croce del Sannio, in provincia di Benevento.

The Caudine Valley, between the province of Avellino and Benevento, falls for the most part in the area of the latter.

The Telesina Valley, in the north and north west of Taburno which it separates from the Matese mounts, extends in the central-western part of the Samnium, crossed by the river Calore and by the stream Titerno.

In the Campanian Apennines, in the province of Benevento, the Valley Vitulanese extends to the slopes of the Taburno Camposauro massif, which it encircles amphitheatrically.