Aspen Mountain is a ski area in the western United States, located in Pitkin County, Colorado, just outside and above the city of Aspen. Situated on the north flank of Aspen Mountain, its summit elevation is 11,212 feet above sea level. Aspen Mountain forms the end of Richmond Ridge, a long ridge that extends ten miles south at approximately 11,000 ft to j…Aspen Mountain is a ski area in the western United States, located in Pitkin County, Colorado, just outside and above the city of Aspen. Situated on the north flank of Aspen Mountain, its summit elevation is 11,212 feet above sea level. Aspen Mountain forms the end of Richmond Ridge, a long ridge that extends ten miles south at approximately 11,000 ft to join the main spine of the Elk Mountains.