
Fort Collins, United States of America · Saturday 17 October 2026
The event covers a distance of approximately 26.7 miles for the full marathon and 13.4 miles for the half marathon, taking place primarily on dirt singletrack trails with a small portion on rocky paths and dirt roads. The course begins at the Blue Sky Trailhead at Horsetooth Mountain Park, situated west of Fort Collins, Colorado.
Adjusted Time
4:44:09
Time difference: +44.1 minutes compared to a flat, road, temperate course.
On our difficulty model, Blue Sky Marathon plays about 37 minutes slower than an average road marathon for a 3:30 runner. It ranks #129 hardest of 1150 marathons we analyse, and #66 of 575 in United States of America. Use the calculator above to see the exact adjusted time for your own goal pace.
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 Blue Sky Marathon | Difference |
|---|---|---|
| 3:00:00 | 3:21:17 | +21:17 |
| 3:30:00 | 4:02:05 | +32:05 |
| 4:00:00 | 4:44:09 | +44:09 |
| 4:30:00 | 5:27:22 | +57:22 |
| 5:00:00 | 6:11:40 | +1:11:40 |
| 5:30:00 | 6:57:00 | +1:27:00 |
| 6:00:00 | 7:43:17 | +1:43:17 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Blue Sky Marathon is a full marathon held in Fort Collins, United States of America. It is scheduled for Saturday 17 October 2026. The course is run on road surface with 1064m of total climbing, with its high point near 1982m above sea level. For registration and full race details, visit the official Blue Sky Marathon website.
This is a very challenging course with 1064m of total climbing - well above the average road marathon - topping out around 1982m above sea level. Hill training is essential, and you should expect a slower finish time than on a flat course.
Based on historical weather data for October, the expected race day conditions are as follows. Near-ideal running temperatures are expected, ranging from -1°C to 21°C. This temperature range is widely considered optimal for marathon performance, allowing efficient heat dissipation without cold-related issues. There is a low chance of rain (0%), so dry conditions are likely.
Blue Sky 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 Blue Sky Marathon against other marathons to find the right race for your goals.
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