Trail Running calendar near Brighton 2025-2026

The HRCA Backcountry Wilderness Half Marathon is an annual 13.1-mile trail race held in Highlands Ranch, Colorado, featuring a scenic single-loop course through the Douglas County East/West trail and the Backcountry Wilderness Area. The race offers a challenging route on dirt, gravel, and singletrac..

Bingo! Trail Party, hosted by the Human Potential Running Series, takes place at May Farms in Byers, Colorado. It features five levels: Level 1 (6–10 miles), Level 2 (8–20 miles), Level 3 (10–42 miles), Level 4 (10–54 miles), and Level 5 (18–54 miles), with a 9 PM time limit and a 300-runner cap. Th..

Louisville Trail Race in Louisville, Colorado returns for its 12th year, offering a Half Marathon, 10K, and 5K on scenic trails around Louisville and the Flat Irons. The mostly dirt courses pair gentle elevation with two longer climbs on the half, plus a shorter hill in the 10K and 5K, all out-and-b..

Colorado Cold Rush Ultra is held in Colorado Springs, CO, offering 50K, half marathon, and 10K options. The course begins at Bear Creek Regional Park, climbs historic High Drive, and runs along Gold Camp Road to a turnaround near Gold Camp/Old Stage Road, rewarding runners with sweeping views and th..

Thumbs Up Vertical Challenge takes place in Estes Park, Colorado, on December 6, 2025. The race uses the Thumb Open Space trail, a 2km out-and-back course with 540 feet of vertical gain per lap. The route is 100% single-track with switchbacks, steps and steep rocks, offering views of Longs Peak, Mou..

Located at Staunton State Park in Pine, Colorado, Sawmill Trail Runs offers three distances: 50k, 16-mile, and 8-mile. The event, now in its 8th edition, starts and finishes at the Ranch Hand Group Picnic Area. With a capped field of 250, the race combines scenic, challenging terrain across Colorado..

USCSA Cross Country Ski Racing Festival, hosted by Colorado Mesa University at Snow Mountain Ranch Nordic Center in Granby, Colorado, on January 24–25, 2026, brings collegiate teams together with junior skiers for a two-day Nordic festival. Races include a 15 km classic (collegiate and independent h..

Race The Ranch is a snowshoe race held at the Snow Mountain Ranch YMCA property in Granby, Colorado on April 4, 2026. The event offers three distances: 50k 25k 5k The 50k route uses less-known trails on the property and includes Pete's Loop. Course maps and stated elevation gains are: 5k one lap..

Run the Ranch is an annual trail running event held at the scenic Sylvan Dale Guest Ranch in Loveland, Colorado. The race offers a variety of distances including 5K, 10K, and timed trail runs of 4, 6, and 12 hours, with options for solo runners and 4-person relay teams. Participants run on private r..

The Rattler Trail Race, held in Colorado Springs at Palmer Park, offers runners a chance to experience scenic singletrack trails with panoramic views of the city and Pikes Peak. The event features multiple distances: 50K, 25K, 10K, and 5K, catering to various skill levels. The course is known for it..

The Great Western Trail Race, held in Severance, Colorado, offers a variety of running events including a 5K, 10K, half marathon, and a Kids Fun Run. Scheduled for April 18, 2026, this race welcomes participants to enjoy spring racing in a scenic community park setting. The event features chip timin..

Niwot’s Challenge is the 13th annual invitation-only endurance ordeal along the South Platte River in Sedalia, Colorado. It offers three non-standard distances: a ~24-mile Burn Loop (16 hours), a ~50-mile Chief’s Loop (30 hours), and an ~100-mile Deity loop (60 hours). It is not a race but a transfo..

Greenland Trail Races is a multi-distance trail running event held at Greenland Open Space in Larkspur, Colorado. The lineup includes 50K, 25K, 8-mile, and 4-mile races, all run on dirt trails within the scenic open space, offering wide, smooth double-track surfaces and views of Pikes Peak. The cour..

Endure Trail Runs takes place at Mueller State Park in Divide, Colorado, with four events: a 12‑Hour endurance race and standard distances of 10K, Half Marathon, and Marathon. The 12‑Hour race uses a unique “tiny balls” mechanic: runners draw colored balls to determine which loop to run next, tallyi..

The Weld Your Mettle Running Festival, held in Eaton, Colorado, is a multi-day event featuring a variety of running challenges for all levels. Participants can choose from solo or relay races lasting 3, 6, 9, 12, 24, or 36 hours, including a 100-mile ultra with a 36-hour limit. Unique formats like t..

North Fork 50 Mile/50K is an ultramarathon set in the Colorado mountains just southwest of Denver, near Buffalo Creek. The event offers two distances: 50 miles and 50K. The course is 100% soft-surface, comprised mostly of singletrack trails with a few short sections of double-track road.Runners clim..

The Great Divide Ultra, held June 6-7, 2026 in Divide, Colorado, is part of Revenant Running’s festival. Distances offered are 100 mile, 100k, 50k, and 25k. The 100‑mile course is six 14.8‑mile loops plus a 10.5‑mile loop through Mueller State Park on smooth single/double‑track trails, delivering sw..

Summits Trail Runs, the 2nd Annual edition of the Human Potential Running Series, unfolds at Granby Ranch Resort in Colorado’s Rocky Mountains (Granby, CO). The race weekend offers several distances: Elevation Challenge (a 32-hour ascent loop on East Peak), 50k, Marathon, Half Marathon, and 6 Miles,..

Crazy Legs 10k+ Trail Run is held at Devil’s Backbone Open Space in Loveland, Colorado, starting and finishing in the parking lot. The loop course runs through Hidden Valley, Hunter Loop, Laughing Horse Loop, and Wild Loop for roughly 10k+, with a low-key atmosphere. The route is flour-arrow marked..

Timberview Trail Run is held at Lory State Park in Bellvue, Colorado, just outside Fort Collins. The event offers three distances: 5K, 5 Mile, and 10 Mile (the 10M is a double loop of the 5M). Runners traverse scenic forest trails with views of Horsetooth Reservoir and the foothills; the 5K is begin..