Race calendar

Ultra Races in Colorado

28 upcoming Ultra races across Colorado. Run This events are listed first — pick a city below to narrow it down.

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28 races

Fri, Aug 14, 2026

2026 CKF Leadville Trail 100 MTB

Leadville, CO

Outside100.0 mi

Fri, Aug 28, 2026

Continental Divide Trail Run

Steamboat Springs, CO

Outside5.0 mi16.0 mi31.1 mi

Thu, Sep 10, 2026

Flaming Foliage Relay - Idaho Springs to Buena Vista

Idaho Springs, CO

Outside165.0 mi

Fri, Sep 11, 2026

2026 Lake Nighthorse Triathlon - Sprint and Olympic

Durango, CO

Outside16.0 mi32.0 mi

Fri, Sep 11, 2026

Rampart Rager Gravel

Colorado Springs, CO

Outside32.0 mi44.0 mi62.0 mi

Fri, Sep 11, 2026

The Gunni Grinder

Gunnison, CO

Outside120.0 mi60.0 mi30.0 mi

Sat, Sep 12, 2026

Buffalo Bicycle Classic

Boulder, CO

Outside35.0 mi50.0 mi70.0 mi100.0 mi

Fri, Sep 18, 2026

Salida Bike Fest - Salida 76 and the Banana Belt

Salida, CO

Outside76.0 mi47.2 mi35.0 mi

Fri, Sep 18, 2026

Beulah Challenge and OverIt Series

Beulah, CO

Outside10K5K32.4 mi

Tue, Sep 22, 2026

CG Adventure Club - Elevation Everest

Winter Park, CO

Outside22.0 mi42.0 mi

Thu, Sep 24, 2026

Red Feather Trail Jamboree

Red Feather Lakes, CO

Outside50.0 mi31.1 miMarathon94.0 mi

Fri, Sep 25, 2026

West Line Winder

Buena Vista, CO

Outside31.1 mi18.6 mi

Fri, Sep 25, 2026

Mountains to the Desert Classic

Telluride, CO

Outside103.0 mi73.0 mi110.0 mi

Fri, Sep 25, 2026

Estes Epic

Estes Park, CO

Outside31.0 mi15.0 mi62.0 mi

Fri, Sep 25, 2026

Sangre de Cristo Trail Festival

Westcliffe, CO

Outside8.0 mi16.8 mi31.1 mi50.0 mi

Sat, Sep 26, 2026

Sawatch Ascent

Nathrop, CO

Outside31.1 mi

Thu, Oct 1, 2026

Water For People World Water Classic

Anywhere, CO

Outside3.7 mi37.3 mi

Fri, Oct 9, 2026

Suffer Better 10th Annual Fall Trail Runs

Pine, CO

Outside31.1 mi15.5 mi5K

Fri, Oct 16, 2026

Indian Creek Trail Runs

Sedalia, CO

Outside5.5 mi15.0 mi35.0 mi54.0 mi

Fri, Dec 4, 2026

Sawmill Trail Runs

Pine, CO

Outside8.1 mi16.1 mi31.7 mi

Sat, Apr 10, 2027

NoCo Urban Ultra & Relay

Bellvue, CO

Outside50.0 mi100.0 mi

Fri, Apr 30, 2027

Greenland Trail Races

Larkspur, CO

Outside31.1 mi15.5 mi8.0 mi4.0 mi

Fri, May 21, 2027

Samson's Revenge

Estes Park, CO

Outside6.5 mi15.5 mi31.1 mi

Fri, Jun 4, 2027

Weld Your Mettle Running Festival

Eaton, CO

Outside50.0 mi62.1 mi4.3 mi14.0 mi

Fri, Jun 11, 2027

KowTown Gravel

Kremmling, CO

Outside88.0 mi54.0 mi28.0 mi16.0 mi

Fri, Jun 11, 2027

Summits Trail Runs

Granby, CO

Outside6.1 mi13.9 mi27.8 mi33.9 mi

Wed, Jun 23, 2027

Race in the Clouds - Alma Dirt Festival 2027

Alma, CO

Outside38.0 mi26.0 miMarathon22.0 mi

Thu, Jul 8, 2027

Silverheels Trail Runs

Como, CO

Outside10.8 mi19.1 mi38.3 mi53.8 mi