Trail Running calendar near Denver 2025-2026

The Front Range Ultra Dayze is an exciting ultra-running festival taking place in Loveland, Colorado, featuring 100 hours of continuous running. This event invites participants from across the U.S. to engage in various ultra-distance races, including options for 200-mile, 100-mile, and timed events..

The American Heroes Run is a commemorative running event held in Longmont, Colorado, designed to honor the heroes of 9/11 and celebrate patriotism. Participants can choose from various race distances, including a 100-mile run, marathon, half-marathon, 9.11-mile run, and a 5K, all set on a scenic 1.0..

The Black Squirrel Half Marathon, scheduled for September 6, 2025, takes place in Lory State Park, Bellvue, Colorado. This challenging 13.5-mile trail race features a mix of technical and non-technical terrain, with approximately 2,000 feet of elevation gain. Runners will enjoy stunning views of Hor..

Devil on the Divide is a challenging trail running event held in Empire, Colorado, featuring two race options: a 50K and a 22K. Participants will experience breathtaking views of Clear Creek County and the Continental Divide, with the 50K course reaching altitudes over 13,000 feet and over 6,500 fee..

The Cirque Series - Arapahoe Basin is a challenging mountain running event set for September 6, 2025, in Keystone, Colorado. Participants will tackle a 9.4-mile course with an elevation gain of 2,411 feet, starting at 10,780 feet. The race features three divisions: Sport, Expert, and Pro, catering t..

The HRCA Wildcat Mountain Trail Races, scheduled for September 6, 2025, in Littleton, Colorado, features a variety of events including a 10K, 10M, and a Kid's Race. The race begins at the Douglas County East/West trailhead and takes participants through the scenic HRCA Backcountry Wilderness Area. R..

The Breckenridge Oktoberfest 5K is an exciting running event that kicks off the annual Oktoberfest celebration in Breckenridge, Colorado. Set against the stunning backdrop of the changing aspens and beautiful mountain scenery, this 5K trail run takes participants through the picturesque Town of Brec..

The Ned Ned Run is a celebrated annual running event held in Nederland, Colorado, featuring a variety of race options including a Half Marathon, 10K, and 5K. This family-friendly event encourages participants to enjoy the scenic beauty of the area while navigating dirt roads and single track trails...

The Meadowgold 5k &10k will take place in Minturn on Saturday 13 September 2025. You can run between 5 and 11 kilometers.

The Snow Mountain Ranch Trail Race, taking place on September 13, 2025, in Granby, Colorado, is a scenic trail running festival featuring multiple race distances: 50K, 33K, Half Marathon, 10K, and 5K. Set against the stunning backdrop of the Rockies, participants can enjoy the vibrant fall colors an..

The Pony Express Trail Run is a scenic trail running event held at Rampart Reservoir, featuring two distance options: 8.5 miles and 16 miles. Set at an elevation of over 9,000 feet, participants can enjoy beautiful single-track trails, creeks, and the vibrant colors of autumn. The event is intention..

The Pikes Peak Marathon, established in 1956, is the oldest continuously held marathon in the United States. This challenging race takes participants from Manitou Springs, Colorado, to the summit of Pikes Peak, reaching an elevation of 14,115 feet, and back down, covering a total of 26.2 miles. The..

The 24 Hours Of Palmer Lake will take place in Palmer Lake from Saturday 27 September 2025 to Sunday 28 September 2025.

Rocky's Backyard Ultra is an exciting ultra trail running event held at the YMCA of the Rockies in Estes Park, Colorado. This unique race format challenges participants to complete a 4.167-mile loop every hour until only one runner remains. The course features stunning Rocky Mountain scenery, with a..

The Castle Rock Trail Festival, also known as the liveBIG Run, invites participants to challenge themselves on the scenic trails of Philip S. Miller Park and Ridgeline Open Space. This event caters to a wide range of athletes, offering various race options including a 5K, 10K, half marathon, and a 5..

The Bear Chase Race Endurance Festival, taking place at Bear Creek Lake Park in Lakewood, CO, features a variety of race distances including 100K, 50 Mile, 50K, Half Marathon, 10K, and 5K. This event is ideal for both novice and experienced trail runners, offering a mix of challenging terrain and st..

The Above the Clouds Ultra is an annual running event held in Woodland Park, Colorado, featuring 50k and 10k races. Set against the stunning backdrop of Pikes Peak, participants experience the vibrant fall colors and scenic trails of Rampart Reservoir. The course begins in Woodland Park, ascending L..

The Blue Sky Trail Marathon and Half Marathon, scheduled for October 18-19, 2025, takes place in Fort Collins, Colorado, featuring scenic trails between Horsetooth Mountain Park and Devil’s Backbone Open Space. The marathon covers 26.7 miles with an elevation gain of 3,500 feet, while the half marat..

The Bobcat Trail Race, taking place in Palmer Park, Colorado Springs, is a thrilling trail running event featuring multiple distances: 50K, 25K, 10K, and 5K. This race showcases the park's stunning landscapes, including rocky bluffs and panoramic views of the city and Pikes Peak. Originally a Mad Mo..

The Great Trailhead Foot Race features both a 10-mile and a 5-mile race, set against the scenic backdrop of Bear Creek Lake Park in Lakewood, Colorado. Participants can enjoy a mix of single-track and dirt trails while racing. Registration includes park admission, a post-race party with complimentar..