Colorado · Marathon · Half Marathon · 26.7 Miles
Blue Sky Trail Marathon & Half Marathon
Blue Sky Trail Marathon & Half Marathon is a marathon, half marathon, 26.7 Miles and 13.4 Miles event held in Fort Collins, Colorado. It was last held on October 17, 2026 and is usually run in October; the next date hasn't been announced yet. About 1,200 runners take part across all distances.
- Usually held
- October
- Location
- Fort Collins, CO
- Field size
- ~1,200 runners
Race details
- Last held
- October 17, 2026
- Usually held in
- October
- Location
- Fort Collins, Colorado
- Distances
- Marathon, Half Marathon, 26.7 Miles, 13.4 Miles
- Field size
- About 1,200 runners
- Course
- Marathon: ~3,500 ft gain/loss (100% dirt, 90% singletrack); Half Marathon: ~1,800 ft gain/loss. Trail race between Horsetooth Mountain Park and Devil's Backbone Open Space.
- Registration
- runsignup.com
- Official website
- gnarrunners.com
Registration, course & weather
- Registration status
- Registration status as last checked September 25, 2026: open
- Entry fee
- Listed fee for the longest distance, $130 (from gnarrunners.com, checked September 25, 2026)
- Start time
- 7:00 AM MDT
- Course profile
- Out-and-back course; Trail surface; 3491 ft gain, 3491 ft loss (official course data); Not a Boston qualifier
About the Blue Sky Trail Marathon & Half Marathon
Welcome to the Blue Sky Trail Marathon & Half, Fort Collins's original and only trail marathon. Taking place on the trails between Horsetooth Mountain Park and the Devil's Backbone Open Space, the course takes you on a north-south tour of the easternmost hogbacks of Northern Colorado's mighty Front Range. The marathon boasts 3,500 feet of elevation gain/loss, while the half marathon checks in at 1,800 feet, and the route offers a little bit of something for everyone. It is designed to appeal to…
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Guides from the RaceRove blog
- 8 min read How to Choose Your First Marathon A practical checklist for choosing a first marathon based on course, weather, cutoff, travel, field size and support.
- 7 min read How to Find a 5K, 10K, Half Marathon or Marathon Near You A practical way to find running races near you: pick a distance, decide how far you'll travel, read the listing properly and confirm the details before you register.
- 9 min read How to Run a Race in All 50 States How to plan a 50-state running challenge: set your own rules, group states into trips, build a calendar around the seasons, budget for it and keep track of every finish.
- Blog All guides Planning advice for finding, choosing and travelling to races.
Blue Sky Trail Marathon & Half Marathon: common questions
- When is the Blue Sky Trail Marathon & Half Marathon?
- The next date hasn't been announced in the listing yet. The race is usually held in October. Check the organiser's website for the official date.
- Where is the Blue Sky Trail Marathon & Half Marathon held?
- In Fort Collins, Colorado.
- What distances does the Blue Sky Trail Marathon & Half Marathon offer?
- Marathon, Half Marathon, 26.7 Miles and 13.4 Miles.
- How many people run the Blue Sky Trail Marathon & Half Marathon?
- About 1,200 runners across all of its distances. That figure is an estimate of the field size, not an entry cap.
- How do I register for the Blue Sky Trail Marathon & Half Marathon?
- Registration is handled by the organiser at runsignup.com. Entry fees, caps and deadlines are set there.
- Is registration open for the Blue Sky Trail Marathon & Half Marathon?
- Registration status as last checked September 25, 2026: open. Listed fee for the longest distance, $130 (from gnarrunners.com, checked September 25, 2026).
- What time does the Blue Sky Trail Marathon & Half Marathon start?
- 7:00 AM MDT.
- What is the course like at the Blue Sky Trail Marathon & Half Marathon?
- Out-and-back course; Trail surface; 3491 ft gain, 3491 ft loss (official course data); Not a Boston qualifier.
Plan this race in RaceRove
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