Alps

Alps , great mountain system of S central Europe, c.500 mi (800 km) long and c.100 mi (160 km) wide, curving in a great arc from the Riviera coast on the Mediterranean Sea, along the borders of N Italy and adjacent regions of SE France, Switzerland, SW Germany, and Austria, and into Slovenia. Crystalline rocks, which are exposed in the higher central regions, are the rocks forming Mont Blanc, the Matterhorn, and high peaks in the Pennine Alps and Hohe Tauern; limestone and other sedimentary rocks are predominant (but not continuously present) in the generally lower ranges to the north and south. Mont Blanc (15,771 ft/4,807 m) is the highest peak.