"Old" Caleb Greenwood was a Western U.S. fur trapper and trail guide. In 1844 he, along with Isaac Hitchcock, guided the influential Stephens-Townsend-Murphy emigrant party across the Sierra Nevada mountain range. Reputedly 80 years old at the time, on reaching Sutter's Fort he had completed the first overland wagon journey to California. Greenwood, returning east the following year with his two sons, pioneered a new route bypassing the Truckee River Canyon. Wikipedia
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