John Fremont Expeditions 1848 and 1853

An oval black and white historic photo of John C. Fremont, a bearded man with a suit and bow tie.
John C. Fremont

US National Archives

John Charles Fremont (1813–1890) worked for the US Topographical Engineers, crossing the rugged terrain of Colorado on various expeditions. As he worked to create maps and discover potential paths for travel, his tenacity earned him the nickname ‘Pathfinder’.

Fremont was hired in 1848 to find a railroad route from St. Louis to California. With confidence based upon Zebulon Pike’s 1807 expedition, Fremont led a group of men successfully across Mosca Pass into the San Luis Valley in winter, walking past the Great Sand Dunes. However, they then tried to push on through even deeper snow in the San Juan Mountains to the west. The group became separated, and many died of hypothermia, starvation, or attack by Utes. A complex rescue effort saved some of the men.

In 1853, Fremont again tried to find a railroad route through Colorado that would work even in winter months. This time he was successful, crossing the San Luis Valley in December and climbing over the Continental Divide at Cochetopa Pass before continuing on to California. Ironically, after all his work to find a route through the Colorado Rockies, the transcontinental railroad was eventually built through southern Wyoming, a much easier path.

Last updated: August 30, 2023

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