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    Marathon Races in Colorado

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

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    Cities in ColoradoColorado SpringsDenverFort Collins

    23 races

    Sun, Dec 6, 2026

    RunDenver Series 2026-27

    Denver, CO

    Outside5K10KMarathon

    Sun, Sep 27, 2026

    Girls on the Run Rockies Boulderthon SoleMates 2026

    Boulder, CO

    OutsideMarathon10K

    Sat, Oct 3, 2026

    Spooky Sprint - Denver

    Littleton, CO

    Outside50 m1 mile5K10K

    Sat, Oct 3, 2026

    Colorado Springs Marathon, Half, 5K, and Kids K

    Colorado Springs, CO

    OutsideMarathon5K1000 m

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    Sun, Oct 4, 2026

    Windsor Marathon, Half Marathon, 10k, 5k & 1 Mile Run

    Windsor, CO

    OutsideMarathon10K5K1 mile

    Sat, Oct 10, 2026

    Breckenridge RunFest

    Breckenridge, CO

    OutsideMarathon10K5K1 mile

    Sat, Oct 10, 2026

    The Long View Marathon

    Fort Collins, CO

    OutsideMarathon5K

    Sun, Oct 11, 2026

    Durango Marathon

    Durango, CO

    OutsideMarathon

    Sat, Oct 17, 2026

    Blue Sky Trail Marathon & Half Marathon

    Fort Collins, CO

    Outside26.7 mi13.8 mi

    Sat, Oct 31, 2026

    Spooky Sprint - Colorado Springs

    Colorado Springs, CO

    Outside1 mile5K10KMarathon

    Sat, Nov 7, 2026

    Turkey Trails- Denver

    Littleton, CO

    Outside50 m1 mile5K10K

    Sun, Nov 8, 2026

    Turkey Trails - Colorado Springs

    Colorado Springs, CO

    Outside50 m1 mile5K10K

    Sat, Nov 14, 2026

    Lone Tree Reckoning Half and 5K

    Loveland, CO

    OutsideMarathon5K

    Sat, Jan 30, 2027

    Alley Loop

    Crested Butte, CO

    OutsideMarathon10K5K1.9 mi

    Sat, Mar 13, 2027

    22nd Annual Run Through Time Trail Marathon and Half Marathon

    Salida, CO

    OutsideMarathon2.0 mi

    Sat, Apr 24, 2027

    DoNot Stop Half Marathon/5K/10K - Colorado Springs

    Colorado Springs, CO

    Outside50 m1 mile5K10K

    Sun, Apr 25, 2027

    DoNot Stop Half Marathon/5K/10K - Denver

    Denver, CO

    Outside50 m1 mile5K10K

    Sun, May 2, 2027

    The Colorado Marathon

    Fort Collins, CO

    OutsideMarathon10K5K

    Sat, May 15, 2027

    Endure Trail Runs

    Divide, CO

    Outside6.8 mi14.1 mi26.5 mi

    Sat, Jun 5, 2027

    Weld Your Mettle Running Festival

    Eaton, CO

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

    Sun, Jun 6, 2027

    The Steamboat Marathon

    Steamboat Springs, CO

    OutsideMarathon10K805 m

    Fri, Jun 25, 2027

    Race in the Clouds - Alma Dirt Festival 2027

    Alma, CO

    Outside38.0 mi26.0 miMarathon22.0 mi

    Sun, Aug 1, 2027

    Bound for Boston Marathon & Half Marathon - Denver

    Denver, CO

    OutsideMarathon

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    Marathon races by city in Colorado

    Colorado Springs4Denver3Fort Collins3