Boulder Rez Marathon

Boulder, United States • 2 Aug 2025

The Boulder Rez Marathon is a scenic running event held at the Boulder Reservoir in Colorado, featuring a flat course primarily on dirt roads and trails. Participants can choose from various distances, including a marathon, half marathon, 3/4 marathon, and 10K. The race offers stunning views of the reservoir and the Rocky Mountains, making it a picturesque experience for runners. The event is USATF sanctioned and includes features such as early packet pickup, participant shirts, and finisher medals. Awards are given to the top finishers in various age groups, promoting a competitive yet inclusive atmosphere. Visit the organization's website for the most recent information.

Race information

26 mi
200 m+
Marathon
26 mi
200 m+
Marathon Relay
31 km
200 m+
3/4 Marathon
13 mi
200 m+
Half Marathon
10 km
200 m+
10k
Visit the organization's website for the most recent information.
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