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    Running Races in Thornton, CO

    5 upcoming races in and around Thornton. Run This events are listed first — jump to a specific distance below.

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    DistanceAll5K
    Nearby citiesDenverColorado SpringsCentennialFort CollinsArvadaLittletonAuroraWestminsterPuebloBoulderGrand JunctionDurango

    5 races

    Sun, Sep 27, 2026

    RMRR Fall Marathon Training Series #3

    Thornton, CO

    Outside10.0 mi20.0 mi

    Sat, Oct 3, 2026

    I Can 5k

    Thornton, CO

    Outside5K

    Sat, Oct 31, 2026

    I Ain't Scared (of 5k)

    Thornton, CO

    Outside5K

    Sat, Dec 12, 2026

    WinterFest 5k & Fun Run

    Thornton, CO

    Outside5K1200 m

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    Sat, Jun 19, 2027

    Unicorn 5k (North)

    Thornton, CO

    Outside5K1000 m

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