Simplon (sĭmˈplŏn) [key], pass, 6,590 ft (2,009 m) high, in the Lepontine Alps, Valais canton, S Switzerland. It is crossed by the Simplon Road built (1800–1806) by Napoleon I. The Simplon Railway passes through Simplon Tunnel I and II, one of the longest (both 12.3 mi/19.8 km) in Europe. Opened in 1906 and 1922, respectively, the tunnels cross the Swiss-Italian border from Brig to Isella. They have a maximum elevation of 2,313 ft (705 m). The Simplon Pass has been an important trade route between northern and southern Europe since the 13th cent.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
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