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mountain pass and tunnel, at the northern end of the Rhaetian Alps, in western Austria. The pass (at 5,882 feet [1,793 m]) forms a divide between the Danube and Rhine river systems. The region is a noted winter sports area, and the Arlberg technique in skiing was perfected there by Hannes Schneider, who was born at Stuben am Arlberg. A rail tunnel 6.3 miles (10.2 km) long, built in 1880-84, carries an electrified railroad between Langen (Vorarlberg) and Sankt Anton (Tirol); the two towns were connected by a road tunnel 8.7 miles (14 km) in length that opened in 1979.