Dolomites or Dolomite Alps, Alpine group, N Italy, between the Isarco and Piave rivers, named for the dolomitic limestone of which it is composed. Famous for their strikingly bold outline (a stairstep effect created by erosion of alternate layers of soft and hard rock) and for their vivid colors at sunrise and sunset, the Dolomites are ideal for mountain climbing and skiing. Hydroelectricity is produced in the Dolomites. The Marmolada (10,964 ft/3,342 m), the highest peak, has glaciers. Cortina d'Ampezzo and other resorts are among the major tourist centers of Italy.