Upcoming Ultramarathons in Colorado

Endurance Grid lists 13 ultramarathons in Colorado, from November 2026 to October 2027 across 13 cities.

13
Races
13
Cities

Ultramarathon Races in Colorado

The ultramarathon race calendar in Colorado is busiest in May, June, and November, with races most often in Colorado Springs and Golden.

What an ultramarathon is

An ultramarathon is any running race longer than 26.2 miles. The most common distances are the 50K, 50-mile, 100K, and 100-mile — alongside timed events, where you cover as much ground as you can in a fixed window like 6, 12, or 24 hours.

Many ultras run on trails, with aid stations stocked with food, water, and posted cutoff times. For most entrants the goal is to finish, not to race the clock, and hiking the climbs is a normal part of the day.

Frequently Asked Questions

How many ultramarathons are in Colorado?
Endurance Grid's Race Calendar lists 13 upcoming ultramarathons in Colorado across 13 cities, from November 2026 to October 2027.
What ultramarathon distances are offered in Colorado?
Ultramarathons in Colorado include 10 Mile, 100 Mile, 100K, 10K, 4 Mile, 50 Mile, 50K, 8 Mile, and more distances.
When is ultramarathon season in Colorado?
Ultramarathon season in Colorado runs spring through fall. Of the upcoming ultramarathons on Endurance Grid's Race Calendar, the most are in May and June.
Which Colorado cities have ultramarathons?
Ultramarathons in Colorado are held in Bellvue, Colorado Springs, Como, Divide, Eaton, Fairplay, Fruita, Golden, Granby, and Larkspur, plus 3 other cities.

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