Marathon

Blue Sky Trail Marathon

Blue Sky Trail Marathon covers 26.7 miles of Fort Collins singletrack, red-rock hogbacks, and dirt road with roughly 3,500 feet of climbing.

Next raceSaturday, October 17, 2026
Distance categoryMarathon
LocationFort Collins, Colorado
Boston qualifierNo
Get alertsLast checked August 4, 2026

Quick facts

  • 26.7-mile trail marathon with about 3,500 feet of gain.
  • Mostly singletrack between Horsetooth and Devil's Backbone.
  • Nine-hour limit with several intermediate cutoffs.

About the Blue Sky Trail Marathon

Gnar Runners' Blue Sky Marathon connects Horsetooth Mountain Park and Devil's Backbone Open Space. It is designed for experienced trail runners and road runners moving into longer trail racing.

Course

About 90 percent of the route is dirt singletrack, ranging from smooth hardpack to rocky technical sections. The 26.7-mile course gains about 3,500 feet and uses an out-and-back extension toward Devil's Backbone.

Race-day weather

Fort Collins can be crisp and dry in mid-October, but exposed ridges bring sun and wind while shaded trail sections stay cold. Early snow is possible.

Past Blue Sky Trail Marathon dates and results

YearDateStatusResults
2026Saturday, October 17, 2026Upcoming
2025Saturday, October 18, 2025CompletedOpen results
2024CompletedOpen results

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Blue Sky Trail Marathon FAQ

When is the Blue Sky Trail Marathon?

The 2026 Blue Sky Trail Marathon is on Saturday, October 17, 2026.

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