Upcoming Half Marathons in Colorado

Endurance Grid lists one hundred half marathons in Colorado, from September 2026 to August 2027 across 34 cities.

100
Races
34
Cities
13
Sports

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Running races in Colorado

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Frequently Asked Questions

How many half marathons are in Colorado?
Endurance Grid's Race Calendar lists 100 upcoming half marathons in Colorado, in 34 cities, from September 2026 to August 2027.
How long is a half marathon?
A half marathon is a running race where athletes run 13.1 miles long (21.1 kilometers) for time.
Which Colorado cities host half marathons?
Half marathons in Colorado are held in Centennial, Colorado Springs, Arvada, Denver, Westminster, Fort Collins, Littleton, Boulder, Buena Vista, and Durango, plus 24 other cities.
What other race distances are available in Colorado?
Beyond half marathon, Colorado races cover a wide range of distances. Colorado also has 5Ks, 10Ks, and 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.