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 Rock Hawk Trail Races, taking place in Castle Rock, CO, feature a variety of distances including 50K, 25K, 10K, and 5K. Set against the scenic backdrop of Miller Park and Ridgeline Trail systems, the event offers thrilling yet manageable trails suitable for both novice and experienced runners. P..

The Rattler Trail Race, taking place in Colorado Springs, features three race distances: 50K, 25K, and 10K. Set in the scenic Palmer Park, participants will experience breathtaking views of the city and Pikes Peak while navigating technical trails with unique rock formations. The course is designed..

The Great Western Trail Race, taking place in Severance, Colorado, features a variety of running events including a 5K, 10K, half marathon, and a Kids Fun Run. This event celebrates Northern Colorado's newest trail, connecting Windsor, Severance, and Eaton. Participants can enjoy a festive atmospher..

The Can't Be Mad Running Festival, taking place in Erie, CO, offers a variety of running events including a 10K, 5K, a 3-hour timed event, and a Kid's 1K, with both in-person and virtual options available. The course features a flat and fast off-road cross-country style route with scenic views of th..

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..

The Royal Gorge Groove is an exciting trail running event taking place in Cañon City, Colorado, on April 26, 2025. Participants can choose from various distances, including 50K, 30K, 20K, 12.5K, 5K, and a Kids Run, all starting and finishing at the scenic Royal Gorge Ranch & Resort. Runners will exp..

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..

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..

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..

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..

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..

The Mountain Ridge Trail Race, taking place on May 10, 2025, in Highlands Ranch, Colorado, offers a variety of distances for trail running enthusiasts, including a 21-mile, half marathon, 10K, and 5K. Celebrating its 11th year, the race features scenic dirt and single-track trails with manageable el..

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 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 Ram Party Trail Runs, scheduled for May 17, 2025, in Colorado Springs, CO, offers a variety of race distances including 55 Mile, 60K, 50K, 24K, and 15K. Set against the stunning backdrop of Rampart Reservoir and Pikes Peak, this event promises an unforgettable trail running experience. Participa..