Boulderthon Marathon
Boulderthon Marathon race day weather
Cool start, warming throughout
Runners will face a temperature rise from 50°F at the start to 75°F by the finish, with light winds under 6 mph making it a non-factor. With average humidity around 38%, conditions are favorable for most of the race, but runners should consider pacing adjustments as they approach the warmer temperatures. The gently rolling terrain will be most challenging in the later miles, particularly between mile 11 and 12 where the descent may lead to a quick temperature increase.
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Boulderthon Marathon route and elevation
The Boulderthon Marathon course has about 845 ft (258 m) of climbing. It is hillier than 76% of the marathon courses racecast.io has mapped, measured by what the hills cost in time. The hardest mile is mile 22, with 83 ft (25 m) of climbing and a 1.6% average grade.
Biggest climbs
- Miles 7.8 to 9.4: climbs about 115 ft (35 m).
- Miles 20.9 to 22: climbs about 95 ft (29 m).
- Miles 22.5 to 23.7: climbs about 95 ft (29 m).
What the hills cost
- 3:30 on a flat course is about 3:32 here (2 minutes slower).
- 4:00 on a flat course is about 4:02 here (2 minutes slower).
- 4:30 on a flat course is about 4:32 here (2 minutes slower).
Hills only, priced mile by mile on the course map. The pace calculator above adds the race-day weather.
Even-effort splits for a 3:30, 4:00 or 4:30 finish
| Mile | Climb | Descent | 3:30 | 4:00 | 4:30 |
|---|---|---|---|---|---|
| 1 | 0 ft | 48 ft | 7:44 | 8:51 | 9:57 |
| 2 | 2 ft | 56 ft | 7:44 | 8:50 | 9:56 |
| 3 | 13 ft | 27 ft | 7:52 | 8:59 | 10:08 |
| 4 | 21 ft | 13 ft | 8:00 | 9:09 | 10:17 |
| 5 | 5 ft | 33 ft | 7:50 | 8:57 | 10:03 |
| 6 | 13 ft | 23 ft | 7:53 | 9:01 | 10:09 |
| 7 | 85 ft | 30 ft | 8:24 | 9:35 | 10:47 |
| 8 | 76 ft | 27 ft | 8:20 | 9:32 | 10:44 |
| 9 | 18 ft | 3 ft | 8:03 | 9:12 | 10:21 |
| 10 | 58 ft | 28 ft | 8:10 | 9:20 | 10:30 |
| 11 | 0 ft | 81 ft | 7:38 | 8:44 | 9:49 |
| 12 | 37 ft | 82 ft | 7:46 | 8:52 | 9:58 |
| 13 | 61 ft | 35 ft | 8:09 | 9:18 | 10:29 |
| 14 | 62 ft | 31 ft | 8:11 | 9:22 | 10:32 |
| 15 | 6 ft | 44 ft | 7:47 | 8:54 | 10:00 |
| 16 | 18 ft | 35 ft | 7:52 | 8:59 | 10:07 |
| 17 | 24 ft | 31 ft | 7:54 | 9:02 | 10:10 |
| 18 | 24 ft | 22 ft | 7:58 | 9:06 | 10:13 |
| 19 | 8 ft | 4 ft | 7:58 | 9:06 | 10:15 |
| 20 | 29 ft | 20 ft | 8:00 | 9:09 | 10:18 |
| 21 | 72 ft | 37 ft | 8:13 | 9:24 | 10:34 |
| 22 | 83 ft | 0 ft | 8:38 | 9:51 | 11:06 |
| 23 | 37 ft | 25 ft | 8:02 | 9:11 | 10:19 |
| 24 | 61 ft | 13 ft | 8:20 | 9:32 | 10:43 |
| 25 | 0 ft | 66 ft | 7:41 | 8:46 | 9:53 |
| 26 | 34 ft | 21 ft | 8:02 | 9:11 | 10:19 |
| Last 0.2 | 10 ft | 0 ft | 1:51 | 2:07 | 2:23 |
Explore the Boulderthon Marathon course with the weather and your pace along the route, or compare it with other races.
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About the Boulderthon Marathon
Named among the Best Fall Marathons by Runner's World, #5 Best Half Marathon in the US by Active, as well as #1 Best in Colorado and one of the "Most Beautiful Marathons in the World" by HalfMarathons.Net, Boulderthon drew over 6,000 runners from all 50 states and 18 countries in 2023, and has doubled in size every year since its inception. Source
