are generally divided into the Western and the Eastern Alps. The division is along the line between Lake Constance and Lake Como, following the rivers Rhine, Liro and Mera. The Western Alps are higher, but their central chain is shorter and curved; they are located in Italy, France and Switzerland. The Eastern Alps belong to Italy, Austria, Switzerland, Germany, Liechtenstein and Slovenia. The highest peak of the Western Alps is Mont Blanc, at 4,808 m (15,774 ft). The highest peak of the Eastern Alps is Piz Bernina, at 4,049 m (13,284 ft). The Dufourspitze, 4,634 m (15,203 ft) and Ortler, 3,905 m (12,812 ft), are the second-highest, respectively.

The main chain follows the watershed from the Mediterranean Sea to the Wienerwald, passing over many of the highest and most famous peaks. From the Colle di Cadibona to Colle di Tenda it runs westwards, before turning to the northwest and then, near the Colle della Maddalena, to the north. Upon reaching the eastern Swiss border, the line of the main chain heads nearly east-northeast, a heading it follows until its end near Vienna.

The Union Internationale des Associations d'Alpinisme (UIAA) has defined a list of 82 "official" Alpine 4,000-meter (13,123 ft) summits. The list contains many subpeaks with little prominence, but important for mountaineering. Four-thousanders with at least 1 km prominence are:

The higher regions of the Alps were long left to the exclusive attention of the people of the adjoining valleys even when Alpine travellers began to visit these valleys. The two who first explored the regions of ice in the Pennine Alps were the naturalist H.-B. de Saussure and the Benedictine monk of Disentis Placidus a Spescha.