Blue Sky Trail Marathon, Fort Collins, CO

  • Start: Blue Sky Trailhead, Horsetooth Mountain Park
  • Distance: 26.5 miles with ~3,500′ of vertical gain and ~3,500′ of descent
  • Mode of Transportation: Bipedal
  • Date: October 2, 2016
  • Start Time: 7:00 AM
  • Cut Off: 9 Hours at 4:00 PM

Welcome to the 9th running of the Blue Sky Marathon, Fort Collins’ 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. With 3,500 feet of elevation gain and an equal amount of elevation loss, the route offers a little bit of something for everyone. It is designed to appeal to both veteran trail runners and those looking to experience their first trail racing adventure. The generous nine hour cut-off should ensure a successful day for everyone.

The course is 100% dirt and 90% sweet Colorado singletrack. The terrain ranges in difficulty from smooth dirt trail to  technical rock gardens.  A small portion of the route is on smooth dirt road (no motor vehicle access) and gravel bike path, with the meat of the running done on the beautiful and distinctive redstone hardpack of the Blue Sky Trail.

After the race, kick back and enjoy the always-popular barbeque and generous sponsor giveaways.

Recent Posts

2016 Black Squirrel & Blue Sky Training Runs

Blue Sky Trail Marathon Course

Photo by Eric Lee

Gnar Runners will be hosting several informal training runs leading up to the Black Squirrel Half Marathon and the Blue Sky Marathon.

Black Squirrel Half Marathon Training Runs
Thursday 8/18 and 9/1 starting at 6pm at the Timber Trailhead in Lory State Park.
4.5, 8, 9.5, and full 13.1 mile route options are available.
Follow us on Facebook here or join the Fort Collins Trail Runners Group for more info.

Blue Sky Marathon Long Run
Sunday 9/4 starting at 7:30am at the Blue Sky Trailhead
We’ll have an informal potluck social gathering back at the trailhead at about 11:30-Noon after the run. More info is online here:


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