The Dolomites are a mountain range located in north-eastern Italy. It is a part of Southern Limestone Alps and extends from the River Adige in the west to the Piave Valley in the east. The northern and southern borders are defined by the Puster Valley and the Sugana Valley (Val Sugana). The Dolomites are nearly equally shared between the provinces of Belluno, South Tyrol, and Trentino.