At this crossing on the North Platte River, wagons, carts, livestock, and emigrants forded the river during organized migrations through the Rocky Mountain West. In the early 1840s, congressional pressure to occupy the Oregon Territory and the lure of fertile, unclaimed land led many families to uproot and travel west, as settling the Pacific Northwest was considered essential to American possession of the continent. The discovery of gold in California in 1848 drew fortune seekers racing to the gold fields, and later gold and silver discoveries in Idaho and Montana increased the westward movement. Known as Red Buttes or Red Hills crossing, this valley provided shade, forage, campsites, and a place to repair equipment before the rocky route ahead. After following the Platte and North Platte Rivers for nearly five hundred miles, pioneers left the river here to avoid rugged narrows upstream and take the shortest route to the Sweetwater Valley. The floodplain often lay underwater during spring runoff or after sudden thunderstorms, and in some years dozens of wagons waited on the opposite bank until high water fell back to sandy channels. On June 23, 1846, James Cayman, traveling east from California, saw the valley dotted with people, horses, cattle, wagons, and tents, with thirty wagons trying to cross a river that could not be forded and using poor material to build rafts that required two trips to carry one loaded wagon.