Ottawa Marathon
Ottawa Marathon race day weather
Warming up, strategic pacing needed
Runners will face a temperature rise from 59°F at the start to 71°F by the finish, with humidity averaging 60%. A light headwind will affect the early miles, particularly from miles 1-3 and 7, requiring runners to conserve energy. As conditions warm, adjusting pace and hydration frequency will be crucial, especially during the rolling terrain where wind changes frequently occur.
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Ottawa Marathon route and elevation
The Ottawa Marathon course has about 1,493 ft (455 m) of climbing and 1,496 ft (456 m) of descent, and finishes near the elevation it starts. It is hillier than 55% of the marathon courses racecast.io has mapped, measured by what the hills cost in time. The hardest mile is mile 13, with 213 ft (65 m) of climbing and a 1.3% average grade.
Biggest climbs
- Miles 10.8 to 11.7: climbs about 100 ft (30 m).
- Miles 12.5 to 12.8: climbs about 135 ft (41 m).
- Miles 14.6 to 16: climbs about 100 ft (31 m).
What the hills cost
- 3:30 on a flat course is about 3:31 here (1 minute slower).
- 4:00 on a flat course is about 4:01 here (1 minute slower).
- 4:30 on a flat course is about 4:31 here (1 minute 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 | 49 ft | 70 ft | 7:52 | 9:00 | 10:08 |
| 2 | 74 ft | 83 ft | 7:56 | 9:04 | 10:11 |
| 3 | 57 ft | 66 ft | 7:56 | 9:04 | 10:12 |
| 4 | 13 ft | 21 ft | 7:56 | 9:04 | 10:12 |
| 5 | 105 ft | 106 ft | 7:58 | 9:05 | 10:14 |
| 6 | 72 ft | 51 ft | 8:08 | 9:19 | 10:28 |
| 7 | 61 ft | 70 ft | 7:56 | 9:03 | 10:12 |
| 8 | 19 ft | 34 ft | 7:54 | 9:03 | 10:10 |
| 9 | 97 ft | 61 ft | 8:16 | 9:26 | 10:37 |
| 10 | 74 ft | 72 ft | 7:59 | 9:07 | 10:16 |
| 11 | 81 ft | 132 ft | 7:46 | 8:53 | 9:59 |
| 12 | 84 ft | 63 ft | 8:08 | 9:18 | 10:28 |
| 13 | 213 ft | 146 ft | 8:32 | 9:45 | 10:58 |
| 14 | 37 ft | 79 ft | 7:48 | 8:55 | 10:02 |
| 15 | 57 ft | 101 ft | 7:48 | 8:55 | 10:01 |
| 16 | 65 ft | 5 ft | 8:28 | 9:41 | 10:54 |
| 17 | 17 ft | 29 ft | 7:55 | 9:03 | 10:11 |
| 18 | 28 ft | 31 ft | 7:58 | 9:05 | 10:13 |
| 19 | 43 ft | 59 ft | 7:54 | 9:02 | 10:10 |
| 20 | 56 ft | 37 ft | 8:07 | 9:17 | 10:27 |
| 21 | 56 ft | 55 ft | 7:58 | 9:06 | 10:14 |
| 22 | 36 ft | 56 ft | 7:54 | 9:01 | 10:09 |
| 23 | 52 ft | 49 ft | 7:59 | 9:08 | 10:16 |
| 24 | 44 ft | 38 ft | 8:01 | 9:10 | 10:19 |
| 25 | 55 ft | 38 ft | 8:06 | 9:16 | 10:25 |
| 26 | 60 ft | 66 ft | 7:57 | 9:04 | 10:13 |
| Last 0.2 | 13 ft | 3 ft | 1:50 | 2:06 | 2:21 |
Explore the Ottawa Marathon course with the weather and your pace along the route, or compare it with other races.
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About the Ottawa Marathon
The Ottawa Marathon is held in late May in downtown Ottawa, Ontario, as part of Ottawa Race Weekend. The course starts at City Hall, heads west along Wellington Street, crosses the Chaudiere Bridge into Gatineau, Quebec, and returns over the Alexandra Bridge before following Colonel By Drive to the finish on Queen Elizabeth Drive. It is a World Athletics Elite Label race and a Boston Marathon qualifier, run alongside a half marathon, 10K, 5K and shorter events. Source
