Trail Running calendar near Keystone 2026-2027

Experience the scenic single track trails of Steamboat Springs during the Emerald Mountain Trail Run. Choose between the 4 mile or 12k distances through aspen groves to support the local Boys and Girls Club.

Multiple trail races and a family obstacle run take place on Castle Rock ridgeline trails, with timed 5K to 50K options, chip timing, finisher medals and proceeds from the liveBIG race supporting the town’s Therapeutic Recreation Program.

The Camp 4 Coffee Cart to Cart Trail Race will take place in Crested Butte on Saturday 3 October 2026. You can run between 10 and 19 miles.

A six-hour trail challenge in Littleton where runners complete a 5K each hour for six hours, totaling 18 miles if completed. Trail terrain, hourly elimination, tiered patches and medals, and national leaderboard prizes highlight the format.

A Halloween themed community event in Aspen on October 4, 2026, with a timed 5.6K run and a 1 mile walk around Koch Park and Marolt open space. Leashed dogs are welcome and net proceeds benefit the Friends of the Aspen Animal Shelter.

Four trail races across Colorado Springs parks with increasing distances, chip timing, and series awards for runners who complete all four events.

Multiple trail distances at Staunton State Park on October 10, 2026, from a steep 5K to a 50K ultramarathon, plus a 25K FishSlappers division that includes catching a trout; proceeds support conservation organizations.

A loop endurance event near Castle Rock, Colorado honoring two women with long lives. Choose **104 miles** or **52 miles** on a 3.25-mile loop, with solo and relay options plus camping, food trucks, and live music.

Run the Rocks is a fundraising event at Red Rocks Park and Amphitheatre in Morrison, Colorado on October 11, 2026. It offers a 5k and a 1.3 mile family course and raises funds for lung disease education, advocacy and research.

Indian Creek Trail Runs in Sedalia, Colorado on October 17, 2026 offers multiple trail and ultra distances through montane forests, aspen groves, red rock formations and prairie vistas with city views from several viewpoints.

Trail races at Bear Creek Lake Park offering 5 miles or a two-lap 10 miles on single-track dirt. Registration includes park admission, a finisher meal and refreshments; 10 mile finishers receive a commemorative mug.

Four trail races across Colorado Springs parks with increasing distances, chip timing, and series awards for runners who complete all four events.

Methodist Mountain Ultra The Methodist Mountain Ultra (MMU) is a trail race set on the Methodist Mountain trail system near Salida, Colorado. It takes place at the northern end of the Sangre de Cristo mountains. The event features two dista..

Trail races at Bear Creek Lake Park on Oct 25 2026 featuring 5 km, 15 km, a 5+15 double and a Kids 1 km. Mostly dirt single and double track with steep climbs, marked courses and included postrace items for adult distances.

MonsterDASH Louisville on Oct 25, 2026 offers a new half marathon plus 5k, 10k and a kids mile with costume contests, expo, and themed runner perks.

A Halloween themed 5k and 10k through historic downtown Erie and Coal Creek trails, with a kids Goblin Run and BOLDERBoulder qualifier status. The event supports the Erie Optimist Club as its primary fundraiser.

Four trail races across Colorado Springs parks with increasing distances, chip timing, and series awards for runners who complete all four events.

Experience 13.1 miles of singletrack trails and hills in the Highlands Ranch Backcountry Wilderness Area. Enjoy custom medals and a post race pancake breakfast while competing for cash prizes in various categories.

Trail races at Starsmore Visitor & Nature Center on November 8, 2026, with chip-timed 4-mile and untimed 2.5-mile courses on Columbine Trail; proceeds support Friends of Cheyenne Cañon and leashed pets are allowed on the trail.

Trail races in Louisville, CO offer a half marathon, 10K and 5K on mostly dirt out and back courses with mountain views. The event features aid stations, limited onsite parking and a family friendly post race atmosphere.