segment of the Central Alps lying north of the Upper Rhône River and south of the Brienzer and Thunersee (lakes) in Bern and Valais cantons of southwestern Switzerland. The mountains extend east-northeastward from the bend of the Rhône near Martigny-Ville to Grimsel Pass and Haslital (valley of the upper Aare River). Many peaks rise to more than 12,000 ft (3,660 m); Finsteraarhorn (14,022 ft), Jungfrau, and Aletschhorn are among the highest. Of the numerous glaciers in the range, the Aletsch is one of the longest in the Alps. The Bernese Alps are crossed by the Lötschen, Gemmi, and Pillon passes and the Lötschberg (railway) Tunnel. The magnificent Alpine scenery has helped establish the nearby resorts of Interlaken, Grindelwald, Mürren, Wengen, Kandersteg, and Gstaad. Mountain climbing has long been a popular activity in the region.