River, 255 mi (410 km) long, the longest in Italy after the Po .
It rises below the Resia Pass and flows southeast through the Venosta valley. After receiving the Isarco River at Bolzano, it turns south across the Po lowlands to enter the Adriatic Sea south of Chioggia. It supplies hydroelectric power in its upper Alpine section and irrigation for the Veneto . Its floods, notably those of 1951 and 1966, do great damage and require constant control of the riverbank. The Adige has been the scene of many battles, especially in the Austrian-Italian campaign of 1916.