The Adige has its origins underneath Passo Resia and is the largest river of South Tyrol.
The Adige river, which runs from South Tyrol to the Adriatic sea, is the second largest of Italy. The Adige river has got a length of 415 km from its origins in the forest above the village of Resia, running through the Val Venosta, past the city od Bolzano to the Bassa Atesina. Several other rivers such as the Passirio and the Isarco rivers empty into the Adige. At Salorno, the Adige flows to the Adriatic sea, where many inhabitants of South Tyrol spend their summer holiday.
Once upon a time along the Adige there was one of the main trade routes, connecting the cool north with the sunny south. As far as the water quality between Merano and Bolzano is concerned, it has been assessed with level two. Between the Lago di Muta and Glorenza, however, the level is even higher, while class three is only achieved in the surroundings of Merano due to recently constructed purification plants. The so-called diatome index reaches level two in Val Venosta and one in the surroundings of Merano and Bolzano. This parameter has been specified with level one between Bolzano and Salorno, while the diatome index is one.