Courses · IRONMAN · Hokkaido, Japan
177.9 km measured along the road and 4638 m of climbing read off the ground, in 13 climbs.
Predict your time on this courseYour weight, your watts for each kind of slope, your position. Nothing to upload.
A model, not a measurement. What it can show depends on the numbers above — what you typed, and what your files recorded — and on assumptions this page states; anything it cannot stand behind says so rather than drawing a tidier line.
Each piece named by what the ground is: the climbs, the flats and the descents.
| Piece of road | Length | Slope | Rise |
|---|---|---|---|
| Flat, 13.2 km from km 0.0 | 13.2 km | — | 5 m |
| Climb, 2.6 km at 2.4% from km 13.2 | 2.6 km | 2.4% | 64 m |
| Flat, 3.9 km from km 15.8 | 3.9 km | -1.4% | — |
| Climb, 5.1 km at 8.2% from km 19.7 | 5.1 km | 8.2% | 420 m |
| Descent, 2.8 km at 12.3% from km 24.8 | 2.8 km | -12.3% | — |
| Flat, 1.4 km from km 27.7 | 1.4 km | 0.6% | 8 m |
| Descent, 2.4 km at 2.9% from km 29.1 | 2.4 km | -2.9% | — |
| Flat, 9.0 km from km 31.5 | 9.0 km | — | — |
| Climb, 2.3 km at 2.8% from km 40.4 | 2.3 km | 2.8% | 67 m |
| Flat, 1.4 km from km 42.8 | 1.4 km | — | — |
| Climb, 2.8 km at 12.2% from km 44.2 | 2.8 km | 12.2% | 345 m |
| Descent, 5.7 km at 6.4% from km 47.0 | 5.7 km | -6.4% | — |
| Flat, 13.8 km from km 52.8 | 13.8 km | — | — |
| Climb, 2.6 km at 2.5% from km 66.6 | 2.6 km | 2.5% | 64 m |
| Flat, 3.9 km from km 69.2 | 3.9 km | -1.4% | — |
| Climb, 5.1 km at 8.2% from km 73.1 | 5.1 km | 8.2% | 420 m |
| Descent, 2.8 km at 12.3% from km 78.2 | 2.8 km | -12.3% | — |
| Flat, 1.4 km from km 81.0 | 1.4 km | 0.6% | 8 m |
| Descent, 2.4 km at 2.9% from km 82.4 | 2.4 km | -2.9% | — |
| Flat, 9.0 km from km 84.8 | 9.0 km | — | — |
| Climb, 2.3 km at 2.9% from km 93.8 | 2.3 km | 2.9% | 67 m |
| Flat, 1.4 km from km 96.1 | 1.4 km | — | — |
| Climb, 2.8 km at 12.2% from km 97.5 | 2.8 km | 12.2% | 345 m |
| Descent, 5.7 km at 6.4% from km 100.3 | 5.7 km | -6.4% | — |
| Flat, 13.8 km from km 106.1 | 13.8 km | — | — |
| Climb, 2.6 km at 2.5% from km 119.9 | 2.6 km | 2.5% | 64 m |
| Flat, 3.9 km from km 122.5 | 3.9 km | -1.4% | — |
| Climb, 5.1 km at 8.2% from km 126.4 | 5.1 km | 8.2% | 420 m |
| Descent, 2.8 km at 12.3% from km 131.5 | 2.8 km | -12.3% | — |
| Flat, 1.4 km from km 134.3 | 1.4 km | 0.6% | 8 m |
| Descent, 2.4 km at 2.9% from km 135.7 | 2.4 km | -2.9% | — |
| Flat, 9.0 km from km 138.1 | 9.0 km | — | — |
| Climb, 2.3 km at 2.8% from km 147.1 | 2.3 km | 2.8% | 67 m |
| Flat, 1.4 km from km 149.5 | 1.4 km | — | — |
| Climb, 2.8 km at 12.2% from km 150.9 | 2.8 km | 12.2% | 345 m |
| Descent, 5.3 km at 7.9% from km 153.7 | 5.3 km | -7.9% | — |
| Climb, 5.0 km at 8.5% from km 159.0 | 5.0 km | 8.5% | 420 m |
| Descent, 2.8 km at 12.3% from km 164.0 | 2.8 km | -12.3% | — |
| Flat, 1.4 km from km 166.8 | 1.4 km | 0.6% | 8 m |
| Descent, 2.4 km at 2.9% from km 168.2 | 2.4 km | -2.9% | — |
| Flat, 7.3 km from km 170.6 | 7.3 km | — | — |
Predict your time on this courseThis page describes the road. How long it takes depends on who rides it.
How the road was measured
The length is measured along the course file's own trace, because the mapped roads covered too little of it to measure along. Expect it to be out by as much as a GPS trace usually is: a few tenths of a percent.
The climbing is read off a terrain model of the ground, averaged along the road, rather than off a barometer, which cannot tell a change in the weather from a hill. The file's own altimeter said 2906 m, near enough the same road.
The course as described from the course IRONMAN published for 2026. watts & time is not connected with the event or its organisers; a course changes from year to year, so check the current one before you plan on it.
177.9 km with 4638 m of climbing, in 13 climbs. The distance is measured along the course file's own trace, because the mapped roads did not cover enough of it, and the climbing is read off a terrain model of the ground rather than a barometer, which drifts with the weather, so a head unit will often show slightly different figures.
In the order you meet them: Climb, 2.6 km at 2.4% from km 13.2; Climb, 5.1 km at 8.2% from km 19.7; Climb, 2.3 km at 2.8% from km 40.4; Climb, 2.8 km at 12.2% from km 44.2; Climb, 2.6 km at 2.5% from km 66.6; Climb, 5.1 km at 8.2% from km 73.1; Climb, 2.3 km at 2.9% from km 93.8; Climb, 2.8 km at 12.2% from km 97.5; and 5 more.
That depends on you, so the page does not guess: open the course in the predictor. Set your weight, the power you will hold on each kind of slope and the position you will ride in, and it answers with the time and the band around it, climb by climb. Nothing to upload: the course is already there.