Dyer Mountain is a 13,862-foot summit in Colorado’s Mosquito Range, part of the central Rocky Mountains, rising about 5.9 miles east of Leadville on the divide between Lake and Park counties. Recognized as a Colorado thirteener, it is significant for both its high elevation and its place along the crest that separates regional watersheds. The mountain also carries historical meaning through its name, which honors frontier preacher John Lewis Dyer and connects this alpine peak to the human story of Colorado’s mining-era frontier.