The Calore (108 km), Irpino to distinguish it from the homonym river of Lucania, finds its sources on the Accellica Mountain in the Picentini chain, in the cities of Montella and Cassano Irpino.

50 kilometers long, the Sabato flows in Irpinia area. It starts on the Colle Finestra del Monte Terminio, and close to Altavilla Irpina it marks for a while the border between the provinces of Avellino and Benevento, where it keeps its watercourse. It receives water from some torrents, of Vallone Barra and Fenestrelle (11 km), which passes through the city of Avellino.

It is the second river of Southern Italy due to its volume of water. The Sele (64 km) rises on the north-eastern part of the Monte Plafagone (foothill of the Cervialto), at an altitude of 420 meters, in the district of Caposele.

The ancient Aufidus, who, according to the legend, was surpassed by the elephants of Hannibal thanks to the bridge built close the actual Lioni, finds its source in the wood of Piano dell’Angelo, at 715 meters of altitude, close to Torella dei Lombardi.

Mentioned by Pliny the Elder, the Cervaro river which starts from Daunia mountains in Puglia, for part of its way flows in Irpinia, in the borders with the province of Foggia, in the upper part of the valley which bears its name.

The mud boils in the barren expanse which occupies part of the valley formed by the Miscano river near Montecalvo Irpino.