Trail Running calendar near Denver 2024-2025

The Leadville Trail 100 Mile Run, known as the "Race Across the Sky," is a prestigious ultramarathon held annually in Leadville, Colorado. Established in 1983, it challenges participants with a grueling 100-mile out-and-back course that features extreme elevation changes, reaching a peak of 12,600 f..

The Into the Hills Eltuck 5K is part of a series of midweek trail races held at Lory State Park in Bellvue, Colorado. Scheduled for August 19, 2025, this event features a challenging course with a steep climb and descent, making it suitable for both novice and experienced trail runners. Participants..

The Westminster Night Trail, celebrating its 12th year, invites runners to experience a unique nighttime race around Standley Lake in Westminster, CO. Participants can choose from various distances, including 50K, 35K, Half Marathon, 10K, and 5K, all set against the stunning backdrop of Colorado's n..

The Staunton Rocks! Marathon and Half Marathon, scheduled for August 23, 2025, is a premier trail running event held in Staunton State Park, Colorado. Designed by trail runners for trail runners, the race features scenic singletrack trails that showcase the park's natural beauty, including historic ..

The Front Range Ultra Dayze is an exciting ultra-running event taking place in Loveland, Colorado, from August 28 to September 1, 2025. This festival features a variety of ultra-distance races, including 200-mile, 100-mile, and timed events ranging from 12 to 100 hours. Participants can camp at the ..

The Cirque Series at Arapahoe Basin is a thrilling mountain running event scheduled for September 6, 2025. Participants will tackle a challenging 9.4-mile course with an elevation gain of 2,411 feet, starting from the base at 10,780 feet. The route features stunning views and diverse terrain, includ..

The HRCA Wildcat Mountain Trail Races, scheduled for September 6, 2025, in Littleton, Colorado, features a variety of events including a 10-mile race, a 10K, and a Kid's Race. The races take place on scenic dirt trails within the HRCA Backcountry Wilderness Area, offering participants stunning mount..

The Black Squirrel Half Marathon, scheduled for September 6, 2025, takes place in Lory State Park near Fort Collins, Colorado. This challenging 13.3-mile race features approximately 2,000 feet of elevation gain and descent, offering runners stunning views of the Horsetooth Reservoir and the Rocky Mo..

The Snow Mountain Ranch Trail Running Festival, taking place in Granby, Colorado, offers a stunning backdrop for runners of all levels. Participants can choose from various race distances, including a 50K, 33K, Half Marathon, 10K, and 5K, all set against the picturesque scenery of rolling hills and ..

The Pony Express Trail Run is a scenic 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 trails, creeks, and wildlife amidst Colorado's autumn scenery. The race is intentionally ke..

The Pikes Peak Ascent and Marathon, established in 1956, is renowned as America's ultimate challenge, featuring the oldest continually held marathon in the U.S. The marathon covers a grueling 26.2 miles from Manitou Springs to the summit of Pikes Peak, ascending approximately 7,800 vertical feet. Th..

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

The Bear Chase Race Endurance Festival, held 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 stunning v..

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

The Castle Rock Trail Festival is an exciting athletic event that caters to a wide range of participants, from ultra-distance runners to families with children aged 5 to 12. Set against the stunning backdrop of Philip S. Miller Park and Ridgeline Open Space, the festival features various race option..

The Great Trailhead Foot Race 10 Miler is an exciting running event held at Bear Creek Lake Park in Lakewood, Colorado. Participants can enjoy a scenic 10-mile course featuring single-track and dirt trails, all while taking in views of Denver's skyline. The event includes a post-race celebration wit..

The Blue Sky Trail Marathon and Half Marathon will take place on October 18-19, 2025, in Fort Collins, Colorado. This event features a challenging 26.7-mile marathon and a 13.1-mile half marathon, both set against the stunning backdrop of the Colorado Rockies. The courses traverse a mix of dirt sing..

The Indian Creek Trail Runs, part of the Human Potential Running Series, is a celebrated annual event known as the "Fall Classic." Scheduled for October 18, 2025, it features multiple race distances including 50-Mile, 55k, 15-Mile, and 5-Mile options. Set in the picturesque Indian Creek Campground n..

The BINGO! Trail Party is a unique running event organized by the Human Potential Running Series, set to take place at May Farms in Byers, Colorado. This event encourages runners of all abilities to participate in a fun and community-oriented atmosphere. Participants run loops on a scenic course unt..

The Louisville Trail Race, celebrating its 12th year, features a Half Marathon, 10K, and 5K, set against the stunning backdrop of Louisville, Colorado. Known for its scenic trails and welcoming atmosphere, the race offers a mostly flat course with a challenging hill that rewards runners with breatht..