Beginning in 1849, rock quarries visible near this location supplied stone and lime for construction projects at Fort Laramie about 15 miles east. Workers in the quarries were protected by soldiers stationed in fortified rifle pits dug along the crest of the low hill to the northeast, where five pits eighteen to twenty four inches deep formed a well arranged defense perimeter. The pits also overlooked the Cold Spring campground, a popular camping and watering place on the Oregon-California Trail from 1841 to 1868, while Warm Spring lay on the far side of the ridge to the south. These springs were vital to westbound emigrants because the North Platte River, high and muddy with Rocky Mountain snowmelt during the annual emigration season, was unfit to drink for people or animals. A still visible branch of the Oregon Trail lies about 500 feet north of Cold Spring, and nearby landmarks include the Oregon Trail Ruts National Historic Site, Register Cliff State Historic Site, and marked pioneer graves. At the Oregon Trail Ruts, wagon wheel tracks are worn up to five feet deep in a soft sandstone ridge, and at Register Cliff passing pioneers carved their signatures, hometowns, and dates into a mile-long bluff beside the North Platte River. Together these places provide strong visual evidence of the 500,000 westering pioneers who passed this way bound for Columbia River farmland, California gold fields, and the religious freedom of the Great Salt Lake valley.