Boulder Rez Marathon

Boulder, United States • 2 Aug 2025

The Boulder Rez Marathon is a scenic running event held at the Boulder Reservoir in Boulder, Colorado. Participants can choose from various distances, including a marathon, half marathon, 3/4 marathon, and 10K, all set along dirt roads and trails with stunning views of the reservoir and Rocky Mountains. The course is mostly flat, making it accessible for runners of all levels. The event features early and race day packet pick-up, participant shirts, finisher medals, and awards for top finishers in various age groups. Volunteers are also welcomed to support the event. Visit the organization's website for the most recent information.

Race information

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