Trail Running calendar near Denver 2025-2026

The Leadville Turquoise Lake 20K is a scenic running event set around the picturesque Turquoise Lake in Leadville, Colorado. Participants will experience breathtaking mountain views as they navigate a course that combines 6.5 miles of hilly paved roads with 5.5 miles of single-track dirt trails. The..

The Fish Hatchery 5K Trail Run is an exciting running event set in the picturesque surroundings of the Leadville National Fish Hatchery in Colorado. Participants will enjoy a scenic cross-country course that meanders through subalpine forests and around the beautiful Evergreen Lakes and lower Rock C..

The Crazy Legs 10k+ Trail Run is an exciting running event taking place at Devil’s Backbone Open Space in Loveland, Colorado. Scheduled for June 1, 2025, this trail run offers participants a challenging course marked by flour arrows, with hydration stations provided along the route. Runners can enjo..

The adidas Terrex Après 5K Trail Run is an exciting event that kicks off the GoPro Mountain Games weekend in Vail, Colorado. Participants can enjoy a scenic evening run on the trails of Vail Mountain, starting and finishing at Nature Valley Mountain Plaza. This 5K race is designed for runners of var..

The Great Divide Ultra is a premier trail running event held in Divide, Colorado, featuring a variety of distances including 100 miles, 100k, 50k, and 25k. Set against the stunning backdrop of Mueller State Park, participants can enjoy smooth single and double-track trails amidst breathtaking views..

The Garden of the Gods Ten Mile Run® is a premier running event held in Colorado Springs, featuring a challenging 10-mile course that winds through the stunning sandstone rock formations of Garden of the Gods Park. Celebrated for over 45 years, this race attracts participants from across the United..

The adidas Terrex 10K Spring Runoff is an exhilarating trail running event set in the stunning Vail Valley, taking place at an elevation of nearly 9,000 feet. Participants will face a challenging course featuring constant elevation changes and diverse terrain, making it one of the most demanding 10K..

The Summits Trail Runs, hosted at Granby Ranch Resort in Colorado, is an exciting trail running event that features a variety of distances, including ultra options. Participants can choose from courses ranging from 6 to 43 miles, all set against the stunning backdrop of the Rocky Mountains. The even..

The Barr Lake Trail Race, taking place in Brighton, Colorado, on June 14, 2025, is a celebrated running event now in its sixth year. It features one of Colorado's flattest and fastest courses, with minimal elevation gain, making it ideal for both seasoned runners and newcomers. Participants can choo..

Estes Park's Backyard Ultra is a unique ultra-running event set against the stunning backdrop of Lake Estes, Colorado. Participants must complete a distance of 4.252 miles within one hour, every hour, until only one runner remains. This format continues indefinitely, with the last runner standing be..

Ring the Springs is an exciting trail running event set to take place in Colorado Springs, Colorado, on June 21, 2025. This fourth edition offers participants a choice of three challenging distances: 100K, 50K, and 30K, each showcasing the stunning natural beauty of the area. Runners will navigate t..

The Sunset Trail Running Festival, taking place in Gold Hill, Colorado, features a variety of trail races including a 28K, 12K, 5K, and a Kids 1K. This event, organized by The Boulder Watershed Collective and T.E.A.M Boulder, aims to raise funds for wildfire preparation and community resilience init..

The Timberview Trail Run is a scenic trail running event held at Lory State Park in Colorado, featuring three race distances: 5K, 5 Mile, and 10 Mile. Scheduled for June 28, 2025, this event caters to athletes of all levels, including beginners and families, with a beginner-friendly 5K route. Partic..

The Leadville Trail Marathon and Heavy Half is a challenging running event held in the historic mining district of Leadville, Colorado. Participants can choose between a 26.4-mile marathon or a 15.4-mile Heavy Half, both featuring stunning alpine trails and reaching elevations over 13,000 feet at Mo..

The Vail Hillclimb will take place in Vail on Saturday 5 July 2025.

The Alma Foundation Race in the Clouds Dirt Festival is an exciting outdoor event taking place in Alma, Colorado, from July 10 to July 13, 2025. Set at an elevation of 10,600 feet, the festival features a variety of activities including mountain bike racing, trail running, a free kids' race, and an..

Chase the Moon is an exciting 12-hour endurance running event taking place in the Highlands Ranch Backcountry trail system. Participants can choose to run solo or form teams for a relay, with options for 3-person and 5-person teams. The race begins at sunset and continues through the night, illumina..

The Silverheels Trail Runs, part of the Human Potential Running Series, is an annual event taking place in Como, Colorado, featuring a variety of challenging distances including 10-Mile, 19-Mile, 60k, 50-Mile, 100k, and 100-Mile races. Set at an average elevation of over 10,000 feet, the course offe..

The Leadville Silver Rush 50M is a challenging 50-mile trail run that tests participants' endurance and grit against the stunning backdrop of the Rocky Mountains. Set in Leadville, Colorado, the course features approximately 8,000 feet of elevation gain, taking runners through historic mining distri..

The 10K & 5K @ 10,000 Feet will take place in Vail on Saturday 19 July 2025. You can run between 5 and 10 kilometers.