Boulder Rez 3/4 Marathon
Race Day Weather
Comfortable temps, big temp swing
Starting at 60°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. Temps will climb significantly to 79°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing.
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Race Info
The 3/4 Marathon covers 31.65 kilometers, or about 19.7 miles, as three laps of the loop around Boulder Reservoir. It runs mostly on dirt roads and trails, with the course starting and finishing in the reservoir parking lot area on Reservoir Road. Each lap follows the dam, 63rd Street, Monarch Road and 55th Street before returning along 51st Street, with long views of the water and the Rocky Mountains. The course is flat.
