Casentino

thumb|250px|View of the Foreste Casentinesi, Monte Falterona, Campigna National Park The Casentino is the valley in which the first tract of the river Arno flows to Subbiano, Italy.

It is one of the four valleys (alongside Valdarno, Valdichiana, and Valtiberina) in which the Province of Arezzo is divided. Mount Falterona, from which the Arno starts, represents the northern boundary between the Casentino and Romagna. On the east of the valley are the Alpe di Serra and the Alpe di Catenaia, which separate the Casentino from the highest tract of the Valtiberina. On the west there is the Pratomagno, which separates the valley from the Valdarno Superiore. Part of the valley is included in the Foreste Casentinesi, Monte Falterona, Campigna National Park.