Upcoming Marathons in Colorado

Endurance Grid lists fifteen marathons in Colorado, from September 2026 to August 2027 across 13 cities.

15
Races
13
Cities
13
Sports

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Running races in Colorado

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Frequently Asked Questions

How many marathons are in Colorado?
Endurance Grid's Race Calendar lists 15 upcoming marathons in Colorado, in 13 cities, from September 2026 to August 2027.
How long is a marathon?
A marathon is a running race where athletes run 26.2 miles long (42.2 kilometers) for time.
Which Colorado cities host marathons?
Marathons in Colorado are held in Fort Collins, Boulder, Breckenridge, Colorado Springs, Denver, Divide, Durango, Eaton, Loma, and Manitou Springs, plus 3 other cities.
What other race distances are available in Colorado?
Beyond marathon, Colorado races cover a wide range of distances. Colorado also has 5Ks, 10Ks, and half marathons for running races. Additionally, Endurance Grid's Race Calendar also covers other sports, with adventure, road cycling, duathlon, gravel, mountain bike, paddle, rucking, running, swimming, swimrun, trail running, triathlon, and ultra races of various distances.