Trail Running calendar near Bellvue 2025-2026

The Eltuck Valley 12K is part of the Lory Summer Trail Series held at Lory State Park in Bellvue, Colorado. This midweek trail race series offers a range of distances from 5K to 12K, catering to both new and experienced trail runners. The August 26 race features a fast and flat 12K course along the..

Front Range Ultra Dayze is a multi-day ultra-running festival in Loveland, Colorado, centered at Centennial Park and the River’s Edge Natural Area. Event distances range from 200-mile to 50k, plus timed formats up to 100+ hours, with a 200-runner cap. The flat, fast 2-mile loop traverses mostly dirt..

The Calarat Challenge Trail Running Festival takes place in Jamestown, Colorado, at the Cal-Wood Education Center, a nonprofit dedicated to outdoor education. Held over Labor Day weekend, the event features multiple trail races including a half marathon, 10K, 5K, Kids 1K, and combination races like..

The HRCA Wildcat Mountain Trail Races, held in Littleton, Colorado, offer a scenic and challenging trail running experience through the HRCA Backcountry Wilderness Area. Participants can choose from a 10-mile or 10-kilometer course, both featuring 100% dirt trails with varied terrain and stunning mo..

Black Squirrel Half is a 13.5-mile trail race held on Lory State Park trails northwest of Fort Collins, Bellvue, Colorado. The course blends 12 miles of dirt singletrack with 1 mile of dirt road, climbing about 1,500 feet to a west ridge apex before a rapid descent and about 4 miles of rolling singl..

RexRun for PAWSitivity is a pet-friendly trail event in Aurora, Colorado at the Arapahoe County Fairgrounds. It offers a 5K Trail Run, a Family 5K Trail Walk (dogs welcome) and a Kids 1-mile Run/Walk. The day features a pet-centric atmosphere with therapy and patrol K-9 demonstrations, a dog costume..

Devil on the Divide is a trail ultramarathon held in Empire, Colorado, featuring two courses: 50K and 22K. The race showcases sweeping views of Clear Creek County and the Continental Divide, with runners reaching elevations over 13,000 feet and 6,500 feet of climbing on the 50K, and about 3,400 feet..

Nestled in Old Town Nederland, Colorado (elevation around 8,236'), NedNed Trail Fest offers a long-running trail challenge with three race options: a Half Marathon (about 13.3 miles with roughly 1,408 feet of elevation gain on dirt roads and single-track trails), a 10K (about 6.3 miles on dirt roads..

Jelm Mountain Run, held near Jelm, Wyoming, offers a 10-mile out-and-back and a 50k (three laps of the same course). The route climbs from about 7,618 feet to the Infrared Observatory atop Jelm Mountain at over 9,600 feet, with more than 2,000 feet of total elevation gain, on improved jeep roads wit..

Snow Mountain Ranch Trail Race, held at the YMCA of the Rockies in Granby, Colorado, offers distances for all levels: 50K (31.4 miles), 33K (20.2 miles), Half Marathon (12.8 miles), 10K (6.1 miles), and 5K (3.3 miles). The courses are 100% dirt, featuring out-and-back and looping designs through rol..

Demon Dash is a 5K running or walking event held in Arvada, Colorado, featuring a new dirt course at the NAAC for a fresh home and surface. It’s pitched as a fun, community-focused experience suitable for runners and walkers of all ages. This year, the race runs in conjunction with the Demons Invite..

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..

Red Feather Trail Jamboree is a three-day trail running weekend held near Red Feather Lakes, Colorado, starting from the Ben Delatour Scout Ranch. Runners can tackle three distances: 50 miles (≈8,500 ft of gain), 50K (≈4,200 ft), and a Half Marathon (≈1,700 ft), with a 3-day Challenge totaling about..

The Rocky's Backyard Ultra will take place in Estes Park on Saturday 4 October 2025. You can run 4 miles.

Set at Bear Creek Lake Park in Lakewood, Colorado, The Bear Chase Race Endurance Festival offers 100K, 50 Mile, 50K, Half Marathon, 10K, 5K, and the Baby Bear 10K. The dirt trail course consists of smooth single-track with rocky stretches; it's fast by trail standards and not overly technical. Each..

The Great Trailhead Foot Race 10 Miler takes place at Bear Creek Lake Park in Lakewood, Colorado, offering runners a scenic trail experience with single-track dirt paths against the backdrop of Denver’s skyline. Participants can choose between a 5-mile or a challenging 10-mile double-lap course. Reg..

Blue Sky Trail Marathon & Half takes place in Fort Collins, Colorado, on trails between Horsetooth Mountain Park and the Devil’s Backbone Open Space. The event offers a 26.7-mile Marathon with about 3,500 feet of elevation gain/loss, and a 13.4-mile Half Marathon with about 1,800 feet. The course is..

Beware The Bear Trail Races take place at Bear Creek Lake Park in Lakewood, Colorado. The event offers four distances: 5K, 15K, a 5K+15K double, and a Kids 1K race. The courses are mostly dirt, using single and double-track trails with short, steep climbs, rollers, and rugged terrain, providing a so..

Colorado 24 Hour Run takes place in Fort Collins, Colorado, at 4927 E. County Road 36. The event offers multiple distance options: 24-hour, 12-hour, and 6-hour races, plus 24-hour, 12-hour, and 6-hour relays.Runners complete laps on a one-mile dirt loop—the flat, scenic loop you’ll find in Colorado—..

The Colleen De Reuck XC Classic is a cross country running event held annually at Harlow Platts Community Park in Boulder, Colorado. Honoring renowned distance runner Colleen De Reuck, the race promotes health, fitness, and celebrates local Olympians, with 2025 honoring 2012 Olympic marathoner Yoshi..