North Fork 50 Mile

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..

The Above the Clouds Ultra takes place in Woodland Park, Colorado on October 4, 2025. The event offers the following distances: 50k 10k Registration closes on October 1, 2025. Registrations include a gender-specific race shirt, personalized bib and finishers’ award, access to aid stations, and a..

The Bear Chase Race Endurance Festival unfolds at Bear Creek Lake Park in Lakewood, Colorado, and offers six races: 100K, 50 Mile, 50K, Half Marathon, 10K, and 5K (with a Baby Bear 10K variant). The mostly dirt, single-track course is described as fast by trail standards and not overly technical, wi..

The Castle Rock Trail Festival / liveBIG Run is a trail running and walking event on the Ridgeline trail system in Castle Rock, using Philip S. Miller Park and Ridgeline Open Space. The event includes a family obstacle run for children ages 5 to 12 and longer trail races for adult participants. Par..

Suffer Better Fall Trail Runs take place at Staunton State Park, just off Highway 285 near Conifer, Colorado. The event offers four distances: 50K, 25K, a 25K FishSlappers edition, and a new 5K. The course showcases CO’s best trails—lovely, flowing singletrack with significant vertical gain (roughly..

The Indian Creek Trail Runs is scheduled for Saturday, October 18, 2025, at Indian Creek Campground in Sedalia, Colorado. The event includes the following distances: 50-Mile 55k 15-Mile 5-Mile Combined runner capacity is 225. Time limits are 14 hours for the 50-Mile and 55k, and 12 hours for the..