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Colorado
Boulder

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Running Races in Boulder, CO

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

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DistanceAll 5K 10K Half Marathon Marathon

Nearby citiesDenver Colorado Springs Centennial Fort Collins Arvada Littleton Aurora Westminster Pueblo Grand Junction Durango Windsor

7 races

Mon, Sep 21, 2026

Mountain Lions XC Program

Boulder, CO

Outside

Sun, Sep 27, 2026

Running for Children's Rights to Both Parents - 9 of 50 Half Marathons in 50 States - Colorado

Boulder, CO

OutsideMarathon5K10K

Sun, Sep 27, 2026

Girls on the Run Rockies Boulderthon SoleMates 2026

Boulder, CO

OutsideMarathon10K

Thu, Nov 26, 2026

Alpine Bank Boulder Thanksgiving Day 5K

Boulder, CO

Outside5K800 m

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Thu, Dec 31, 2026

Hands & Voices New Year Virtual 5K: Trails to the Summit

Boulder, CO

Outside5K

Sun, May 2, 2027

Emerge 5K

Boulder, CO

Outside5K

Sat, Jun 12, 2027

Alpha 5K Challenge

Boulder, CO

Outside5K

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Other cities in Colorado

Denver44 Colorado Springs35 Centennial32 Fort Collins19 Arvada16 Littleton13 Aurora10 Westminster10 Pueblo8 Grand Junction7 Durango