The City of Idaho Springs is a municipality in the U.S. state of Colorado that is the most populous settlement in Clear Creek County, Colorado. Idaho Springs is located in Clear Creek Canyon, in the mountains upstream from Golden, Colorado, about thirty miles west of Denver. Founded in 1859 by prospectors during the early days of the Pike's Peak Gold Rush, the town was at the center of the region's mining district throughout the late nineteenth century. The Argo tunnel drained and provided access to many lodes of ore between Idaho Springs and Central City. During the late twentieth century, the town evolved into a tourist center along U.S. Highway 6 and U.S. Highway 40, which ascend Clear Creek Canyon through the historic mining district. The town today is squeezed along the north side of Interstate 70, with a historical downtown on its western end and a strip of tourist-related businesses on its eastern end. It also serves as a bedroom community for workers at the Loveland Ski Area farther up the canyon. The town today is the largest community in Clear Creek County, but, for historical reasons, the county seat has remained at Georgetown.