Colfax Marathon
Denver, United States of America · Monday 17 May 2027
The Colfax Marathon is an annual running event held in Denver, Colorado, recognized as Denver's only marathon and one of the largest running events in the Rocky Mountain region. It was established by the cities of Denver, Lakewood, and Aurora to honor Colfax Avenue, which is notable for being the longest main street in the United States.
Difficulty Calculator
h
:m
:s
Adjusted Time
4:04:40
Time difference: +4.7 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain211m
Elevation High1686m
Elevation Low1576m
Weather Forecast
High21°C
Low12°C
Chance of Rain40%
How hard is Colfax Marathon?
Difficultharder than 55% of marathons
Flattest / easiestHardest
On our difficulty model, Colfax Marathon plays about 8 minutes slower than an average road marathon for a 3:30 runner. It ranks #521 hardest of 1151 marathons we analyse, and #274 of 576 in United States of America. Use the calculator above to see the exact adjusted time for your own goal pace.
What will you run at Colfax Marathon?
Estimated finish times on this course versus the same effort on an average road marathon, based on its elevation, surface, and expected race-day temperature.
| Average-course time | On Colfax Marathon | Difference |
|---|---|---|
| 3:00:00 | 3:00:46 | +00:46 |
| 3:30:00 | 3:32:38 | +02:38 |
| 4:00:00 | 4:04:40 | +04:40 |
| 4:30:00 | 4:36:52 | +06:52 |
| 5:00:00 | 5:09:14 | +09:14 |
| 5:30:00 | 5:41:45 | +11:45 |
| 6:00:00 | 6:14:24 | +14:24 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Colfax Marathon 2027 Course Analysis
Colfax Marathon is a full marathon held in Denver, United States of America. It is scheduled for Monday 17 May 2027. The course is run on road surface with 211m of total climbing, with its high point near 1686m above sea level. For registration and full race details, visit the official Colfax Marathon website.
Elevation Profile
With 211m of total climbing, this is a gently undulating course. The elevation changes are manageable for most runners and shouldn't greatly affect your pacing.
Expected Race Day Weather
Based on historical weather data for May, the expected race day conditions are as follows. Moderate temperatures between 12°C and 21°C are expected. While comfortable for most runners, those targeting fast times should pay attention to hydration, as these temperatures can impact performance on race day. There is a moderate chance of rain (40%). Runners may want to prepare for wet conditions but shouldn't expect persistent rainfall.
Surface Type: Road
Colfax Marathon is run on road surfaces, which provide the fastest and most predictable conditions for racing. Road courses allow for consistent pacing and are typically the best choice for a personal best.
Looking for an easier marathon or a tougher challenge? You can also compare Colfax Marathon against other marathons to find the right race for your goals.
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If Colfax Marathon fits your goal, these courses play out about the same on our difficulty model.
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