Nearly all overland travelers on the Platte River Road referred to the massive bluffs beyond Court House Rock and Chimney Rock as Scott's Bluffs. In 1828 as Hiram Scott and his companions were returning from a fur trapping expedition in the Rocky Mountains, Scott fell ill. When he could no longer travel, his companions abandoned him. The following year his skeleton was found near the bluff that today bears the name of Scotts Bluff.
From a distance the bluffs seemed to be an almost impenetrable barrier, but there was a lower and less craggy area to the south. Here the bluffs had eroded into a comparatively smooth ascent that wagons could negotiate. This passageway later became known as Robidoux Pass. The approach was gradual, until the last half mile before the summit, where there was a rise of one hundred feet.
To use this pass travelers had to swing south away from the river and proceed nearly thirty miles before they rejoined the North Platte near Horse Creek. Fortunately springs and nearby cedar trees in the pass provided water and wood. The Robidoux family of fur traders recognized the advantages of the area and built their first trading post nearby in 1848, though the pass did not bear their name until many years later.
The first whites to regularly use Robidoux Pass were trappers and traders, who took their pack trains up the North Platte to the Rocky Mountains in the 1820s. In 1830 the wagons of a fur trading caravan were the first to use the pass and reach the Rocky Mountains, showing the way for the thousands of emigrant wagons to follow.
Despite its water and wood, overland travelers were never satisfied with Robidoux Pass because it took them so far away from the North Platte River. A second gap in the bluffs, today called Mitchell Pass, skirted the base of the highest promontory and lay closer to the river. Historian Merrill Mattes noted, "Up to and including 1850 the Robidoux route was used almost exclusively by the successive waves of fur traders, missionary parties, soldiers, and emigrants. . . . In the year 1851 travel was about equally divided between the two routes. From 1852 onward Mitchell Pass was heavily favored, although Robidoux continued in use occasionally, right up to the period of settlement.
"Thus while Mitchell Pass, at Scotts Bluff National Monument headquarters, can claim to be the main route of the military and freighting trains, the Pony Express, the first transcontinental telegraph and the stagecoach, it was Robidoux Pass which witnessed the coming of the fur traders, the missionaries, the Oregon migration of the 1840's, and, climactically, the unique, ballad-inspiring California gold rush."