Blue Sky Trail Marathon

Fort Collins, United States • 18-19 Oct 2025

The Blue Sky Trail Marathon and Half Marathon, scheduled for October 18-19, 2025, takes place in Fort Collins, Colorado, featuring scenic trails between Horsetooth Mountain Park and Devil’s Backbone Open Space. The marathon covers 26.7 miles with an elevation gain of 3,500 feet, while the half marathon spans 13.4 miles with a 1,800-foot elevation gain. Both courses consist of 100% dirt trails, primarily singletrack, offering a mix of terrain suitable for both experienced and novice trail runners. Participants can enjoy post-race festivities, including food and awards, with generous cut-off times to ensure a successful experience for all. Visit the organization's website for the most recent information.

Race information

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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