part of the Rhaetian Alps in eastern Switzerland along the Italian border, lying southeast of the Engadin (valley of the Upper Inn River). The scenic range rises to Bernina Peak (13,284 feet 【4,049 m】), which was first ascended in 1850 by the Swiss climber Johann Coaz. Bernina Pass (7,638 feet 【2,328 m】), generally closed by snow from November to May, lies 10 miles (16 km) southeast of Saint Moritz and is crossed by a highway and a railway; in 2008 the railway was designated a UNESCO World Heritage site. Part of the range extends northeast into the Swiss National Park. Mountain climbing and winter sports are popular activities.