Ultras in Colorado — 2026

There are 9 ultras in Colorado scheduled for 2026. The next is the High Lonesome 100 in Nathrop on July 17. Colorado ultras run primarily May through September.

DU Splash & Dash

Sun, May 3 · Denver, CO Denver
DU Splash & Dash - Kids RaceDU Splash & Dash - Age Group RaceDU Splash & Dash - Collegiate Race
From $20 Open Closing Soon
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Wild West Relay

Fri, Jul 31 · Fort Collins, CO Fort Collins
Wild West Relay - Get Your Ass Over the Pass - Ultra team (4-6 runners)Wild West Relay - Get Your Ass Over the Pass - Super Ultra team (1-3 runners)Wild West Relay - Get Your Ass Over the Pass - High School Team +1
From $660 Open Closing Soon
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Boulder 2 Fort Collins 2 Nathrop 2 Denver 1 Idaho Springs 1 Walden 1

All Colorado Races

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