Trail Running Calendar Colorado 2025-2026

Welcome to Colorado's premier trail running calendar for 2025-2026! Recognized as a trail runner's haven, Colorado seamlessly blends bustling urban settings with pristine mountain terrains. Whether you're a native, a newbie, or a visitor exploring the Centennial State's running trails, our calendar ensures you don't miss out on any event.

Denver, the renowned Mile High City, beckons runners with its urban-meets-nature charm. Iconic routes like the Cherry Creek Trail zigzag right through the city's pulse. Venturing south, Colorado Springs, dubbed the "Olympic City", boasts of trails skirting the monumental Garden of the Gods. Here, a run transcends the ordinary, offering an experience akin to striking gold.

For those seeking a quiet escape, Aurora presents peaceful reservoir paths, making urban detox achievable. If the allure of academic vibes mixed with nature captivates you, Fort Collins and its famous Horsetooth Reservoir trails won't disappoint. Meanwhile, Lakewood introduces runners to nature's canvas with the Red Rocks painting every run. And let's not forget Boulder, offering a diverse range of trails set against the stunning backdrop of the Flatirons.

The Royal Gorge Groove is a trail running event held in Cañon City, Colorado, featuring races of various distances including 50K, 30K, 20K, 13K, 5K, and a Kids Run. The races start and finish at the Royal Gorge Ranch & Resort, offering stunning views along the rim of the Royal Gorge, 900 feet above..

The Cheyenne Mountain Trail Race, taking place in Colorado Springs, features a variety of distances including 50K, 25K, 7 Miler, and 4 Miler. Set against the stunning backdrop of Cheyenne Mountain State Park, participants will navigate scenic trails that include grassy meadows and wooded areas. The..

May 2025

The Falcon 50 is an annual race series held on May 3, 2025, at the USAF Academy in Colorado Springs, featuring five race options: 50 Miler, Marathon, Military Heavy, Half Marathon, and Military Half-Heavy. Established in 2011, the event showcases scenic and challenging terrain, primarily on dirt tra..

Take 5 in the Garden is an exciting running event held in the picturesque Garden of the Gods in Colorado Springs, CO. Participants can choose between a road race or a trail race, with options including a 5K, 5 Miler, and a 9.5-mile course. The event features closed roads, allowing runners to enjoy t..

The Collegiate Peaks Trail Run, celebrating its 35th anniversary, is a renowned trail running event held in Buena Vista, Colorado. Participants can choose between two challenging distances: 25 miles and 50 miles. Established in 1991, the race features a scenic course that follows single-track and je..

The Greenland Trail Races, set in southern Douglas County, Colorado, features a variety of running events including a 50K ultramarathon, 25K, 8M, and 4M races. Participants can enjoy scenic trails with Pikes Peak as a backdrop, aiming for personal bests on soft dirt paths. The event includes chip ti..

The Mountain Ridge Trail Race, held in Highlands Ranch, Colorado, offers scenic trail running options for all levels, including 5K, 10K, half marathon, and 21-mile courses. Set on the Douglas County East-West Regional Trail, the race features rolling hills, dirt and single-track trails, and manageab..

The Quad Rock 50 and 25 Mile Trail Races, organized by Gnar Runners, will take place on May 10, 2025, in Lory State Park and Horsetooth Mountain Park, near Fort Collins, Colorado. This challenging event features a scenic course with significant elevation gains—over 5,500 feet for the 25-mile race an..

Adventure Fest at 18 Road is a thrilling weekend celebration of outdoor adventure in Fruita, Colorado, designed for participants of all skill levels. Scheduled for May 10-11, 2025, the event features a variety of activities including a trail half marathon, mountain bike races, and a gravel challenge..

Niwot's Challenge is a demanding ultramarathon held in Colorado's Front Range, inspired by the Barkley Marathons. This grassroots event, limited to 40 participants, emphasizes navigation skills as runners traverse mostly off-trail terrain using only a map and compass. The challenge includes various..

The Valkyrie Trail Race is a women's-focused running event held in Cheyenne Mountain State Park, Colorado Springs. Scheduled for May 10, 2025, it offers various distances, including 4 miles, 8 miles, 30K, marathon, and 50K. Participants will enjoy a scenic course that begins on crushed limestone and..

The Fruita Trail Half Marathon is an exhilarating 13.8-mile race set in the stunning desert landscape of Fruita, Colorado. Scheduled for May 11, 2025, this event features a scenic loop course with flowy singletrack, short climbs, and breathtaking views of the surrounding buttes and mesas. As part of..

The Dynafit Boneyard Boogie 5K/13K will take place in Eagle on Saturday 17 May 2025. You can run between 6 and 14 kilometers.

Samson's Revenge is an exciting running event taking place at the YMCA of the Rockies in Estes Park, CO, featuring three race distances: 55k, 27k, and 10k. The course offers a mix of fast single track trails and a challenging ascent to Bible Point, where participants can compete for the King of the..

The Sky Pilots Ouray Backyard Ultra is a unique running event taking place in Ouray, Colorado. Participants tackle a 4.167-mile course, with the challenge of completing each lap within an hour to continue racing. The event continues until only one runner remains, who must complete one additional lap..

The Ram Party Trail Runs will take place in Colorado Springs on Saturday 17 May 2025. You can run between 15 and 55 miles.

The Endure Trail Runs, organized by the Human Potential Running Series, takes place at Mueller State Park in Divide, Colorado. This unique event features a variety of races, including a 10k, Half Marathon, and timed challenges of 12 and 24 hours. Participants in the 12-Hour and 24-Hour events will d..

The Vallecito Lake Heavy Half is a scenic half marathon set around the picturesque Vallecito Reservoir in Colorado's San Juan Mountains. Scheduled for May 17, 2025, this unique race offers participants the chance to run on a course that includes sections typically closed to the public, such as a por..

The Mt Sopris Run-Off is an exciting trail running event held in Carbondale, CO, featuring two race distances: 10 miles and 25k. Scheduled for May 18, 2025, the race takes participants along the scenic "Up & Over" single track trail, starting at Flying Dog Ranch and finishing at Rock Bottom Ranch. T..

The Weld Your Mettle Running Festival is a four-day event taking place in Eaton, Colorado, from May 23 to May 26, 2025. It offers a variety of running challenges suitable for all levels, including a 7K run, ruck, and timed events ranging from 3 to 48 hours, either solo or as part of a relay team. Pa..