The Elk Mountains and West Elk Mountains, near the ski towns of Aspen and Crested Butte, are arguably the most beautiful mountains in Colorado. The combination of jagged peaks, multi-colored rocks, expansive fields of wildflowers, and vast groves of aspen make these mountains pure alpine eye candy.
Elk Mountains
Geology of the Elk Mountains

Much of the Elk Range is composed of sedimentary rocks (sandstone, shale, and limestone) deposited in shallow ancient seas that once covered most of Colorado during the Paleozoic Era around 300 million years ago, and also during the Cretaceous Era about 100 million years ago. Around 70 million years ago this sedimentary rock was thrust upwards during the Laramide orogeny, forming the Elk Range. These uplifted sedimentary rock layers form the picturesque striations and red color visible in the famous Maroon Bells and Pyramid Peak. Around 30 million years ago large volumes of granite magma were injected through the sedimentary rock, visible today in the white/gray colored peaks of Snowmass Mountain, Capitol Peak, and Mount Sopris. All of this was later uplifted again in the last 5 million years like other Colorado ranges.