Trail Running calendar near Longmont 2026-2027

A multi-distance trail event in Greenland Open Space near Larkspur, Colorado offering 50K, 25K, 8M and 4M on dirt double-track trails with aid stations, looped courses, drop-bag access and a virtual race option.

Trail races near Fort Collins offering 25 and 50 mile options on mostly singletrack through Lory State Park and Horsetooth Mountain Park, featuring about 5,500 ft or 11,000 ft of vertical gain, staffed aid stations, and marked trails.

A multi-day running festival near Eaton, Colorado featuring loop-course races from 7K to 100 miles, relay options, a 36-hour virtual race, glamping and on-site amenities including sauna and cold plunge.

Trail races at Granby Ranch Resort in Colorado offer multiple distances from 6.1 miles to 55k and an Elevation Challenge scored by total elevation climbed. Courses run on single-track trails through forests, meadows, and alpine terrain.