Aspen and Snowmass mountains offer wonderful trail running opportunities for all abilities. On steep Aspen Mountain, the 1-mile Ajax Trail is listed as ‘intermediate’. The windy trail gains about 500 feet of elevation over rolling hills, offering great views of town below and passing under the Silver Queen Gondola. Most runners start at the east end in Koch Park and make their way west to where AJAX meets the Ute Trail. Supplement your workout with a hike/run up the steep and challenging Ute Trail to Ute Rock. Another good option is the 2.4 mile East Rim/Cherry Hill Loop at the 11,000 foot summit of Aspen, which can be reached by riding the Silver Queen Gondola (fee required). Note: Elevation!
This trail map is a great resource for the wonderful trail running, hiking, and mountain biking options on Aspen and Snowmass mountains, with ratings and descriptions. On Snowmass, the trails are divided into the Bike Park and Elk Camp sections. Note: Be aware of mountain bikers.