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.
Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 21, 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
| Year | Date | Status | Results |
|---|---|---|---|
| 2026 | Saturday, October 17, 2026 | Upcoming | — |
| 2025 | Saturday, October 18, 2025 | Completed | Open results |
| 2024 | — | Completed | Open results |
Blue Sky Trail Marathon FAQ
When is the Blue Sky Trail Marathon?
The 2026 Blue Sky Trail Marathon is on Saturday, October 17, 2026.
How do I register for the Blue Sky Trail Marathon?
Registration for the 2026 Blue Sky Trail Marathon has not been posted yet.
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