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 Buena Vista Pack Burro Race, held in Buena Vista, Colorado, is a unique 14-mile pack burro running event and the third leg of the 2025 PBR Triple Crown. Participants race alongside their burros, donkeys equipped with pack saddles carrying prospector gear, over challenging terrain that reflects t..

The Into the Hills Eltuck 10K is part of a series of midweek trail races held at Lory State Park in Bellvue, Colorado. Scheduled for August 12, 2025, this event is designed to cater to both novice and experienced trail runners, offering a challenging course with significant elevation gain and stunni..

The San Juan Softie 100 is a challenging 100-mile ultramarathon held in Durango, Colorado, traversing the scenic San Juan Mountains. The course features an average elevation near 10,000 feet and includes over 20,000 feet of vertical gain, making it a demanding mountain race. Participants experience..

The Leadville Trail 100 Mile Run, held annually in Leadville, Colorado, is a legendary ultramarathon known as the "Race Across the Sky." Established in 1983, this grueling 100-mile out-and-back course challenges runners with extreme Rocky Mountain terrain, starting at 10,200 feet and reaching a peak..

The Cheyenne Mountain Run is an annual trail running event held at Cheyenne Mountain State Park in Colorado Springs. Celebrating its 10th year in 2025, the event offers three race distances: 5K, 10K, and 25K. The course features scenic trails within the state park, providing a challenging and enjoya..

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 NoCo Urban Ultra & Relay is a long-distance running event taking place on August 22-23, 2025, along the scenic Poudre River Trail in Northern Colorado. Participants can choose from a 50-mile solo race, a 100-mile solo race, or relay options for both distances, accommodating teams of 2 to 8 runne..

The Rio Grande 100 is an ultramarathon held in South Fork, Colorado, starting and finishing along the Rio Grande River. The challenging 100-mile course traverses the stunning La Garita Mountains, featuring diverse terrain from arid forests to alpine tundra, with four ascents above 12,000 feet. Runne..

The Arrowhead Half Marathon & 5K is a scenic trail running event held in Arrowhead, Colorado, featuring challenging courses through the Arrowhead, Bachelor Gulch, and Beaver Creek Ski Resorts. The half marathon covers approximately 13.7 miles with 2,924 feet of elevation gain, offering runners breat..

The Byers Peak Stampede Half Marathon & 5K Run is an exciting running event set in the stunning Rocky Mountains, just 60 miles from Denver. Scheduled for August 23, 2025, the event features a challenging half marathon and a 5K, catering to athletes of all levels. The courses primarily traverse dirt..

The Telluride Mountain Run, held in Telluride, Colorado, is a demanding mountain race set in the scenic San Juan Mountains. Offering three distances—40 miles, 24 miles, and 13 miles—this event challenges runners with technical terrain including old mining roads, singletrack trails, alpine tundra, ex..

The Continental Divide Trail Run, held in Steamboat Springs, Colorado, offers three trail race distances: 5 miles, 16 miles, and 50 kilometers. The courses traverse beautiful aspen and pine forests with stunning views of the Yampa Valley. The 16-mile race features over 3,500 feet of elevation gain,..

The Westminster Night Trail is an annual night trail running event held at Standley Lake in Westminster, Colorado. Celebrating its 12th year, the race offers multiple distances: 50K, 35K, half marathon, 10K, and 5K, all run on 100% packed dirt trails featuring a mix of single-track and bike paths. T..

The Staunton Rocks! Marathon & Half is a trail running event held at Staunton State Park in Pine, Colorado, in the Front Range Mountains southwest of Denver. The race offers two distances: a marathon (26.3 miles with 4,500 feet of elevation gain) and a half marathon (13.1 miles with 2,200 feet of ga..

The Eltuck Valley 12K is part of the Lory Summer Trail Series, taking place at Lory State Park in Bellvue, Colorado. This event features a series of midweek trail races designed for both novice and experienced runners, offering distances from 5K to 12K. The series aims to provide a fun and low-key a..

Front Range Ultra Dayze is an ultra-running festival held in Loveland, Colorado, featuring a variety of ultra-distance events including 50k, 100-mile, 200-mile, and timed races from 12 to 100 hours. The course is a flat, fast 2-mile loop with 80% dirt trail and 20% pavement, set in Centennial Park a..

The Rock Hawk Trail Races take place at Philip S. Miller Park in Castle Rock, Colorado, featuring distances of 50K, 25K, 10K, and 5K. The courses run on the scenic, rolling trails of Miller Park and the Ridgeline Trail system, offering a mix of challenge and excitement without being overly technical..

The Grand Traverse Mountain Run is a challenging 40-mile point-to-point ultramarathon held in Colorado, running from Crested Butte to Aspen across the Elk Mountains. The course follows the route of the Grand Traverse Backcountry Ski race and features over 6,000 feet of elevation gain, offering a dem..

The Creede Mountain Run, held in Creede, Colorado, is a scenic and challenging mountain race established in 1987. It offers four race distances: 2 miles, 12 miles, 22 miles, and a 50K ultra marathon. Starting at 8,850 feet elevation in the historic mining town, the course ascends through Willow Cree..

The 10k @ 10,000 Feet is a challenging trail running event held at the summit of Rabbit Ears Pass near Steamboat Springs, Colorado. Known for its breathtaking mountain scenery, the race features a 10k course that is actually about 6.8 miles with approximately 1,200 feet of elevation gain and loss. T..