The Rockies were traversed by westward-bound pioneers; the principal U.S. pass across the mountains is South Pass (alt. c.7,550 ft/2,301 m) at the southern end of the Wind River Range, SW Wyoming, which links the Wyoming Basin and the Great Plains with the basins and plateaus W of the Rockies. This pass was followed by the Oregon and Mormon trails. The Santa Fe Trail skirted the southern end of the Rockies. In Canada the important passes are Kicking Horse (alt. 5,539 ft/1,688 m), which carries the Trans-Canada Highway, Crowsnest Pass, and Yellowhead Pass.
Explorers of the U.S. Rockies have included Vasquez de Coronado (1540), Meriwether Lewis and William Clark (1804–6), Zebulon Pike (1806–7), Stephen Long (1819–20), Benjamin Bonneville (1832–35), John Frémont (1843–44), Isaac Stevens (1853), John W. Powell (1868), and Ferdinand Hayden (1871). Leading Canadian explorers were sieur de la Vérendrye (1738–39), Sir Alexander Mackenzie (1792–93), David Thompson (1799–1803), and Simon Fraser (1803–7).