Blue Sky Trail Marathon

Fort Collins, United States • 17-18 Oct 2026

Blue Sky Marathon & Half

The Blue Sky Marathon and Half take place on trails between Horsetooth Mountain Park and Devil’s Backbone Open Space near Fort Collins, Colorado. Courses run north-south along the easternmost hogbacks of the Front Range and range in elevation from about 5,300 ft to 6,500 ft.

Distances:

  • 26.7 miles - about 3,500 ft total elevation gain
  • 13.4 miles - about 1,800 ft total elevation gain

The routes are 100% dirt with roughly 90% singletrack. Terrain includes smooth dirt singletrack, rocky technical sections, a small portion of dirt road and gravel, and the redstone hardpack of the Blue Sky Trail. Wildlife noted on course includes deer, Abert squirrel, and golden eagle.

Aid stations are fully stocked with sports drink, gels, water, soda, salty and sweet snacks, and fruit. Gluten free and vegan alternatives are available for most items but cross-contamination is possible. Runners must carry at least a 16 oz water bottle or bladder; there are no aid station cups.

The marathon has a field cap of 400 and the half has a field cap of 400. Time allowances are stated for each distance and intermediate marathon cut-offs are enforced at specified aid stations. Drop bags are permitted at designated locations and must be labeled; volunteers are not responsible for valuables. The course will be well marked and basic facilities are provided at start/finish areas. Visit the organization's website for the most recent information.

Race information

27 mi
Marathon
13 mi
Half Marathon
Visit the organization's website for the most recent information.
Trail runs nearby

Trail races near Fort Collins in Lory State Park and Horsetooth Mountain Park offering 25 miles (about 5,500 ft gain) and 50 miles (about 11,000 ft gain) on mostly singletrack with staffed aid stations and a well marked course.

Trail races at the YMCA of the Rockies in Estes Park on May 23, 2026 offer 50k, 25k and 10k options. The course centers on a 10 km loop with a 1,200 ft climb at Bible Point and two staffed aid stations.

A multi distance running festival in Eaton, Colorado on May 30 to May 31, 2026 offering races from 7K to 100 Mile plus relay and timed events. The venue uses a 2 mile groomed loop and provides glamping and onsite amenities including sauna a..

A looped 10k plus trail run at Devils Backbone Open Space in Loveland featuring marked singletrack, an aid station near mile three served twice, old school timing with a finish stick, and an awards gathering at Loveland Aleworks.

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