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.

Ouray Mountain Trail Run takes place in Ouray, Colorado, on September 20, 2025, and covers 13 miles of mountainous terrain, starting and finishing at Fellin Park. A fundraiser for Ouray School, it’s hosted by PATT and the HS Outdoor Education Class to support student trips to Moab, Denver, Washingto..

The Mountain Marmot Trail Run, presented by Durango Running Company, is a challenging 12-mile trail race held at Purgatory Resort in Durango, Colorado. The course features a steady climb of about 1,800 feet from the base to the top of Lift 8, followed by a downhill return, showcasing stunning single..

The Pikes Peak Ascent is an uphill endurance race from Manitou Springs, Colorado, to the summit of Pikes Peak. It covers 13.32 miles with a total elevation gain of 7,867 feet. The course is described as not a typical half marathon, but a unique and demanding challenge.The event takes place in Manito..

The Frederick Pack Burro Race is an annual 10K event held in Frederick, Colorado, celebrating the town's Miners Day heritage. The race follows a scenic course starting downtown at Fifth and Oak Streets, heading north along a trail through a tunnel to the Frederick Recreation Area, looping around Mil..

Be Ovary Aware 5K Run/3K Walk is a Colorado Springs charity race benefiting Sue’s Gift Gynecologic Cancer Support. The 17th annual event takes place at America the Beautiful Park, featuring a flat, scenic out-and-back course along Fountain Creek on the Pikes Peak Greenway Trail, starting and finishi..

The Pikes Peak Marathon is the 70th Annual race held in Manitou Springs, Colorado. It covers 26.2 miles with 7,834 feet of elevation gain (and loss), starting in Manitou Springs and climbing to the summit of Pikes Peak before returning to the start. Marketed as America’s Ultimate Challenge, the cour..

Red Feather Trail Jamboree is a three-day trail running weekend near Red Feather Lakes, Colorado, hosted at the Ben Delatour Scout Ranch and surrounding National Forest. The event features three main races: 50-mile (≈8,500 ft gain), 50K (≈4,200 ft gain), and Half Marathon (≈1,700 ft gain), plus a 3-..

Sangre de Cristo Trail Festival is a multi-distance trail-running event held in Westcliffe, Colorado, with start/finish at Greenhorn/Music Meadows Ranch near the Grape Creek Trailhead. The festival features six distances: 8-Mile, 27k, 50k, 50-Mile, 100k, and 100-Mile, all run along the Rainbow Trail..

Golden Leaf Half Marathon, presented by ACG, is the bucket-list race hosted by the Ute Mountaineer and the City of Aspen. The half marathon (approximately 13.1 miles) starts at Fanny Hill in Snowmass and follows the Government Trail through scenic Aspen groves, finishing at Koch Lumber Park in downt..

The West Line Winder is a scenic trail running event held in Buena Vista, Colorado, featuring two race distances: a 50K (30.6 miles) with 4,000 feet of ascent and a 30K (18.1 miles) with 2,080 feet of ascent. The courses traverse buttery singletrack trails, forest roads, and some paved sections, set..

Pagosa Mountain Chile Cha Cha Trail Races in Pagosa Springs, Colorado, offers 5K and 10K trail options on a fresh course at Cloman Park, just minutes from downtown. The gentle, low-elevation loop winds through Ponderosa Pine with clear views of the San Juan Mountains and Pagosa Peak, making it suita..

24 Hours of Palmer Lake is a 24-hour ultramarathon held in Palmer Lake, Colorado, on a 0.82-mile loop atop the Palmer Divide at about 7,240 feet elevation. The event is described as a low-fanfare, community-driven affair, welcoming runners who want to push mental and physical limits in a mountain se..

Estes Epic is a multi-event trail challenge held in Estes Park, Colorado. The weekend features a 50k bike race, a 50k trail run, a Heavy Half Marathon, and the all-in Epic Double (50k MTB and 50k Run). After a six-year break, the race returns with remote, rugged terrain, single-track trails, steep c..

Crested Butte Ultra, in Crested Butte, Colorado, features 50 Miler, 55K, and 35K formats. Runners traverse the Gunnison National Forest on single-track trails through mountain meadows and up to high ridges for wide-open vistas of wildflowers, mountain backdrops, and fall foliage. The event aims to f..

Located in La Veta, Colorado, at the base of the Spanish Peaks in the Cuchara Valley, WILD Wahatoya Runs offers 50K, a heavy half marathon, 8 miles. The 50K weaves through La Veta, along rugged roads with sweeping views of dikes, buttes, and mountains, finishing on restored trails into town for a fe..

Deep Creek Trail Half Marathon is a roughly 13-mile trail race in Telluride, Colorado. The course starts at the beginning of Last Dollar Road near the Telluride Airport, runs to the Deep Creek Corral, then climbs into Aspen-filled woods and follows the Deep Creek Trail back to Telluride. The mostly..

The McGinn Memorial Cross Country Challenge is held annually at Reservoir Hill in downtown Pagosa Springs, Colorado. This event features middle school and high school races, with courses running 3 kilometers for middle schoolers and 5 kilometers for high schoolers. The terrain includes a mix of hill..

The Emerald Mountain Trail Run takes place in Steamboat Springs, Colorado, offering two race distances: a 12k (approximately 7.75 miles) and a 4-mile run. The scenic course starts at the base of Howelsen Hill and winds through aspen-lined single-track trails on Emerald Mountain. The event welcomes h..

The Sawatch Ascent 50k is a challenging high-alpine trail race held in Nathrop, Colorado, showcasing the stunning Sawatch Range. Covering 33 miles with 7,000 feet of vertical gain, the course features a mix of 26 miles of singletrack, paved, and gravel roads, including 12 miles on the Colorado Trail..

14er Fest is a fall trail-running event in Buena Vista, Colorado, featuring two races: an 8.7-mile (14K) course and a 3.1-mile (5K) course. The 14K starts in Buena Vista River Park, crosses the Arkansas River, and climbs the Midland Hill Trail System for over 500 feet of elevation gain, offering pan..