Trail Running calendar near Longmont 2025-2026

We have found 50 Trailruns within 80 miles of Longmont. See below where and when you can find the races.

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 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..

May 2026

The Niwot's Challenge will take place in Sedalia from Saturday 2 May 2026 to Saturday 9 May 2026. You can run between 24 and 100 miles.

The Greenland Trail Races, held annually in May at Greenland Open Space in Larkspur, Colorado, offer four trail running distances: 4 miles, 8 miles, 25K, and the 50K ultramarathon, known as Colorado's fastest 50K. The course features wide, smooth dirt trails through native grasslands, ponds, oak hil..

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..

June 2026

The Crazy Legs Trail Run will take place in Loveland on Sunday 7 June 2026. You can run 10 kilometers.

The Summits Trail Runs, held at Granby Ranch Resort in Colorado's Rocky Mountains, offer a challenging and scenic trail running experience with distances from 6 miles to ultra distances including a 50k and a 12-hour Elevation Challenge. The courses feature rugged alpine terrain, single-track trails,..

The Timberview Trail Run is an annual trail running event held at Lory State Park in Bellvue, Colorado. Celebrating its seventh year in 2026, the race offers three distances: 5K, 5 mile, and 10 mile, catering to all levels from beginners to experienced trail runners. The scenic course features trail..

July 2026

The Silverheels Trail Runs, hosted by the Human Potential Running Series, is a premier trail running event held near Como, Colorado, at an average elevation above 10,000 feet. The event features multiple race distances including 10-Mile, 19-Mile, 60k, 50-Mile, 100k, and 100-Mile, with courses showca..

The Summit 200 is a challenging 200-mile ultramarathon held in Frisco, Colorado, featuring a single loop through Summit County's stunning mountain terrain. The course includes scenic hiking trails, forest roads, and some pavement, with elevations ranging from 9,000 to nearly 13,000 feet and a total..