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Boulder Rez Marathon

Boulder, United States • 15 Aug 2026

Boulder Rez Marathon : event overview

The Boulder Rez Marathon takes place at Boulder Reservoir in Boulder, Colorado on August 15, 2026. Distances offered include:

  • 10K
  • Half Marathon
  • 3/4 Marathon
  • Marathon
  • Marathon Relay

The course runs alongside Boulder Reservoir and stays mostly on dirt roads and trails. The route is described as flat with approximately 200 feet of elevation gain and provides views of the reservoir and the Rocky Mountains. The event is USATF sanctioned, with accurately measured and clearly marked courses and electronic timing results. Participants receive a shirt and finishers receive a medal.

Logistics and awards

Packet pickup is available the day before the race at Fleet Feet Boulder, 2775 Pearl, Boulder, CO, and on race day at the Boulder Reservoir parking lot finish area. There are tiered entry fees that vary by registration date. Volunteers of all ages are welcome; volunteers under 13 must be accompanied by a parent or guardian during their shift. Awards are given to the overall top three male and female finishers and in age groups: 19 & under; 20-29; 30-39; 40-49; 50-59; 60-69; 70-79; 80+. Visit the organization's website for the most recent information.

United States Colorado Boulder

Race information

Website
Marathon
Marathon Relay
Marathon
Marathon
31 km
3/4 Marathon
Half Marathon
Half Marathon
10 km
10k
Visit the organization's website for the most recent information.
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