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Blue Sky Trail Marathon

Fort Collins, United States • 18-19 Oct 2025

The Blue Sky Trail Marathon & Half Marathon, held in Fort Collins, Colorado, offers a scenic and challenging trail running experience through Horsetooth Mountain Park and Devil’s Backbone Open Space. The marathon covers 26.7 miles with 3,500 feet of elevation gain, while the half marathon spans 13.4 miles with 1,800 feet of elevation gain. The course features 90% singletrack trails on distinctive redstone hardpack, ranging from smooth dirt paths to technical rock gardens, with some dirt road sections. Designed for both seasoned trail runners and newcomers, the event provides generous time cut-offs and well-stocked aid stations. Post-race festivities include a barbecue and sponsor giveaways. Visit the organization's website for the most recent information.

United States Colorado Fort Collins

Race information

Website Registration
26 mi
3500 m+
Blue Sky Trail Marathon
13 mi
1800 m+
Blue Sky Trail Half Marathon
Visit the organization's website for the most recent information.
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