Half Marathon Races in Colorado

RMRR Spring Marathon Training Series #1

Mar 29, 2026 Thornton, CO

10 Mile20miTwo-Race Bundle Short - 10mi2-Race Bundle Long - 20mi

From $20.00 Open

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RMRR Spring Marathon Training Series #2

Apr 11, 2026 Thornton, CO

MTS#2 - 10 MileMTS#2 - 20 Mile

From $20.00 Open

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Race in the Clouds - Alma Dirt Festival 2026

Jun 25, 2026 Alma, CO

Highschool/Middle School Short Course (6.1miles)Trail 10KNEW 26 Mile Mountain Bike Relay (Teams of Two)Highschool/Middle School Long Course (13 miles)Trail 1/2 MarathonOff Road Duathlon (Run/Ride)26 Mile -ish Mountain Bike40 Mile -ish Mountain Bike13 Mile Mountain BikeFREE Kids Mountain Bike and Trail RunWeekend Camping

From $0.00 Closing Soon Open

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