Denver Colfax Marathon
Denver Colfax Marathon is the big urban marathon in Denver, known for city landmarks, relay energy, and a race weekend that stretches well beyond the full.
Quick facts
- Denver's primary urban marathon weekend, with major relay participation.
- The marathon course is listed as a Boston Marathon qualifier.
- Race-result hub remains live on the event site for race-week searches.
- Best fit for runners who want city-race energy more than a controlled downhill setup.
Is registration open for the 2027 Denver Colfax Marathon?
Registration for the 2027 Denver Colfax Marathon is open.
About the Denver Colfax Marathon
The Denver Colfax Marathon is a city marathon in the fullest sense, with a weekend footprint and relay presence that make the event feel bigger than a single 26.2-mile race. It is the kind of race where the city's identity matters as much as the timing mats.
Course
The marathon is built as an urban tour, not a downhill specialist race or a quiet suburban loop. Between the city setting, relay traffic, and Denver altitude, the course asks for more patience than runners sometimes expect from a big-profile metropolitan event.
Race-day weather
Denver can offer a cool start, but the altitude, dry air, and fast-rising sun change the effort quickly. If the day brightens early, the course can feel harder than the clock suggests.
Past Denver Colfax Marathon dates and results
| Year | Date | Status | Results |
|---|---|---|---|
| 2027 | Sunday, May 16, 2027 | Upcoming | — |
| 2026 | Sunday, May 17, 2026 | Completed | Open results |
| 2025 | Sunday, May 18, 2025 | Completed | Open results |
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Denver Colfax Marathon FAQ
When is the Denver Colfax Marathon?
The 2027 Denver Colfax Marathon is on Sunday, May 16, 2027.
Is registration open for the 2027 Denver Colfax Marathon?
Registration for the 2027 Denver Colfax Marathon is open. View the official registration details at runcolfax.org.
Is Denver Colfax Marathon a Boston qualifier?
Yes. Denver Colfax Marathon is a Boston Marathon qualifier. To use the result, you must run the certified full-marathon course within the qualifying window and meet the current standard for your age and gender. Meeting the standard lets you apply but does not guarantee entry, and net-downhill courses can receive a time adjustment under current B.A.A. rules. Review the Boston qualifying times and downhill-course rules, or browse upcoming Boston qualifier marathons.
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