Trail Running calendar near Castle Rock 2026-2027

Sheep Mountain Trail Runs in Fairplay, CO offers 50 mile, 50k and half marathon courses at high elevation with technical trails and forest roads. The event includes stocked aid stations, a finisher medal, drop down options and a 16 hour tim..

Mountain trail races in Winter Park CO on August 1 2026 with 50K, 21K and 10K courses through high-alpine singletrack and town finishes.

Two Brothers Up and Down in Idaho Springs on August 1, 2026 features steep out and back courses on dirt and pavement with major elevation gain for 5k and 10k.

A pack burro race in Buena Vista Colorado on Aug 2 2026 with 13.1 mile and 7.3 mile courses offered both with and without burros. Burro teams must meet specific equipment and conduct rules and finishers receive a gift and a meal.

Trail races of 5K, 10K, and half marathon on Frisco Peninsula trails with lakeshore finishes at Dillon Reservoir on August 8, 2026.

A community benefit trail event in Castle Rock with a 5K and a 1 Mile Walk raising funds for a family affected by spinal muscular atrophy.

Trail run at Rampart Reservoir with 8 mile and 16 mile options on single track and rocky sections. Entry is limited to 150 and registration closes August 5, 2026.

Community 5K and Walker/Kids Mile at Mountain View Fellowship in Strasburg, fundraising for the SHS cross country team on a mixed-surface course with age group awards.

A traditional pack-burro race in Leadville, Colorado at over 10,000 feet where each team is one runner and one burro carrying mining tools. The long course is about 21 miles and a shorter 6 to 8 mile course is planned.

Trail run on August 12, 2026 at Carter Park in Breckenridge offering short and long course entries with adult youth and non binary categories.

A mostly dirt and trail race along Boulder Reservoir in Boulder, Colorado, with about 200 feet of elevation gain. Distances range from a 10K to a full marathon, plus a relay option.

Two fully supported trail ultras in Roxborough State Park with technical singletrack, significant elevation gain, and a finish at the Sharptail Trailhead.

Experience the trails of Cheyenne Mountain State Park with three race distances ranging from a 5K walk to a 25K mountain challenge. This chip timed fundraiser supports park conservation through scenic and high elevation courses.

Westminster Trail Races on August 15 2026 offers multiple trail distances around Standley Lake on packed dirt with lake and mountain views.

Summit Grays and Torreys Peaks in this 8.8 mile Colorado endurance event. Participants must carry a 20lb dry load while tackling 4,101 feet of elevation gain.

A 10K out and back on the first and last 3.1 miles of the LT100 Run in Leadville, featuring high altitude terrain and one aid station at the turnaround.

The Rocky Mountain Milestone Challenge will take place in Granby from Wednesday 19 August 2026 to Sunday 23 August 2026. You can run between 13 and 100 miles.

A 100 mile out-and-back ultramarathon in Leadville with over 15,000 feet of ascent, high alpine passes, 11 aid stations, a lottery entry and belt buckle finish traditions.

Trail-based chip timed half marathon and 5K near Fraser, Colorado, on unpaved roads and trails, with aid stations and proceeds supporting the Shining Stars Foundation.

A trail race at Staunton State Park offering 26.3 mile and 13.1 mile courses over mostly singletrack with significant elevation gain, well marked trails, capped fields, and fully stocked aid stations.