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Boulder Rez Marathon

Boulder, United States • 2 Aug 2025

The Boulder Rez Marathon, held at Boulder Reservoir in Boulder, Colorado, offers a scenic and mostly flat course with only 200 feet of elevation gain. Runners enjoy trails and dirt roads alongside the reservoir, with stunning views of the water and the Rocky Mountains. The event features multiple distances including a 10K, half marathon, 3/4 marathon, full marathon, and a marathon relay.

It is a USATF-sanctioned race with accurately measured and clearly marked courses. Participants receive a shirt and finisher medal, and awards are given to top finishers overall and across various age groups. The event emphasizes a welcoming atmosphere and reliable race results. Visit the organization's website for the most recent information.

United States Colorado Boulder

Race information

Website
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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