The longest river of Southern Italy with its 175 kilometres rises in Molise, at Rocchetta a Volturno and runs for a long way in the Apennine region, of which, after the Ponte 25 archi, marks the border with Campania.

With a surface of just over a square kilometer, the enchanting Lake of Letino was created at the beginning of the twentieth century in order to feed the hydroelectric power station of Prata Sannita.

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.