Denver Colfax Marathon
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Event overview
The Denver Colfax Marathon weekend takes place in mid-May 2026, with the main race day on May 17, 2026 and the 5K on May 16, 2026. A two-day race expo will be held at Empower Field at Mile High on the Friday and Saturday of the weekend. The 2026 event marks the race's 20th year; limited-edition 20th year jackets are available. Registration for the event opens in mid/late August. The event includes charity programs and relay divisions that together award an average of $150,000 annually to charities.
Races and course details
The weekend includes multiple races and relay divisions, with these distances:
- 26.2 miles - Marathon (Denver's only marathon; Boston qualifier)
- 13.1 miles - Half Marathon
- 10 miles - Urban 10 Miler
- 5K - Colfax 5K
- Marathon Relay - teams of five, with Open, Corporate, Government, and Public School Teachers divisions
Course notes: the marathon route runs through Empower Field at Mile High twice, passes along waterways, and goes through a fire station. The half marathon includes a one-mile section through the Denver Zoo and runs along Colfax and 17th Avenue into a finish party. The Urban 10 Miler is a point-to-point course that starts at RMCAD and finishes in City Park; bibs include an RTD ticket for return transit. An awards evening and additional weekend events are part of the race program. Visit the organization's website for the most recent information.