Maroon Bells is just 10 miles West of Aspen, Colorado.
More than 300 million years of geologic activity, including sedimentation, uplift and erosion by wind, water and ice, are credited to the creation of Maroon Valley. According to the US Forest Service, the mountains received their distinctive maroon coloring from the weathering of hematite, an iron-bearing mineral, while Maroon Lake occupies a basin that was sculpted by Ice-Age glaciers.