Biwako Marathon course & pace calculator
A point-to-point race from Ojiyama Stadium in Otsu along the east shore of Lake Biwa, crossing the Omi Ohashi bridge and turning back just before the Lake Biwa Ohashi bridge to finish on the Karasuma Peninsula. Mostly flat and exposed along the lake. This profile uses a Strava route export of the 2025 race, so treat it as third-party reference geometry.
- Climb
- 42 m
- Descent
- 38 m
- Low – high
- 84 m – 91 m
- Terrain at 3:00
- +0:17
- Typical start
- 6°C
- Sub-3 needs
- 2:59:43 flat
Course time calculator
Type h:mm:ss or use the step buttons.
6°C at your start → 10°C at the finish · dew point 0°C
Heat is scored with shade WBGT from temperature and humidity, starting to cost time above about 15°C (59°F) WBGT. Slower runners lose more because they are out longer. Wind, sun and rain are not modelled.
Certified distance only. Switch on to count the metres lost to corners, crowds and aid stations.
Same effort all the way: slower up the climbs, faster down the descents.
- Flat course
- 2:59:43
- Terrain
- +0:17
- Weather
- ±0:00
- Biwako finish
- 3:00:00
Average 4:16 /km on course · 4:16 /km flat
Elevation profile
42 m up, 38 m down. Hover or tap the chart for the grade and your clock time at any point.
- Climb 2%+
- Climb 0.8–2%
- Flat
- Descent 0.8–2%
- Descent 2%+
- 1Ojiyama Stadium · 0.0 km
- 2Turnaround before Lake Biwa Ohashi · 34.6 km
- 3Karasuma Peninsula finish · 42.2 km
Course splits for 3:00:00
Even-effort splits with the selected weather. Climbing and descent are per split, from the smoothed profile.
| Split | Pace | Split time | Clock | Up / down |
|---|---|---|---|---|
| 1 km | 4:17 | 4:17 | 4:17 | +2 m / −1 m |
| 2 km | 4:15 | 4:15 | 8:32 | +0 m / −2 m |
| 3 km | 4:16 | 4:16 | 12:48 | +2 m / −1 m |
| 4 km | 4:16 | 4:16 | 17:04 | +1 m / −2 m |
| 5 km | 4:16 | 4:16 | 21:19 | +1 m / −1 m |
| 6 km | 4:17 | 4:17 | 25:36 | +2 m / −1 m |
| 7 km | 4:17 | 4:17 | 29:53 | +2 m / −0 m |
| 8 km | 4:15 | 4:15 | 34:08 | +0 m / −2 m |
| 9 km | 4:15 | 4:15 | 38:23 | +0 m / −1 m |
| 10 km | 4:15 | 4:15 | 42:38 | +0 m / −1 m |
| 11 km | 4:16 | 4:16 | 46:55 | +1 m / −1 m |
| 12 km | 4:16 | 4:16 | 51:11 | +1 m / −1 m |
| 13 km | 4:16 | 4:16 | 55:26 | +1 m / −1 m |
| 14 km | 4:15 | 4:15 | 59:42 | +0 m / −1 m |
| 15 km | 4:16 | 4:16 | 1:03:58 | +1 m / −0 m |
| 16 km | 4:16 | 4:16 | 1:08:14 | +1 m / −0 m |
| 17 km | 4:18 | 4:18 | 1:12:32 | +3 m / −0 m |
| 18 km | 4:15 | 4:15 | 1:16:47 | +0 m / −2 m |
| 19 km | 4:15 | 4:15 | 1:21:02 | +0 m / −1 m |
| 20 km | 4:16 | 4:16 | 1:25:17 | +0 m / −0 m |
| 21 km | 4:16 | 4:16 | 1:29:33 | +0 m / −0 m |
| 22 km | 4:15 | 4:15 | 1:33:48 | +0 m / −1 m |
| 23 km | 4:16 | 4:16 | 1:38:04 | +1 m / −0 m |
| 24 km | 4:15 | 4:15 | 1:42:19 | +0 m / −1 m |
| 25 km | 4:16 | 4:16 | 1:46:35 | +1 m / −1 m |
| 26 km | 4:16 | 4:16 | 1:50:51 | +1 m / −1 m |
| 27 km | 4:16 | 4:16 | 1:55:07 | +1 m / −1 m |
| 28 km | 4:16 | 4:16 | 1:59:23 | +1 m / −1 m |
| 29 km | 4:16 | 4:16 | 2:03:39 | +1 m / −1 m |
| 30 km | 4:15 | 4:15 | 2:07:55 | +0 m / −1 m |
| 31 km | 4:15 | 4:15 | 2:12:10 | +0 m / −1 m |
| 32 km | 4:15 | 4:15 | 2:16:26 | +1 m / −2 m |
| 33 km | 4:16 | 4:16 | 2:20:42 | +1 m / −1 m |
| 34 km | 4:17 | 4:17 | 2:24:59 | +3 m / −2 m |
| 35 km | 4:16 | 4:16 | 2:29:15 | +2 m / −2 m |
| 36 km | 4:16 | 4:16 | 2:33:31 | +2 m / −1 m |
| 37 km | 4:16 | 4:16 | 2:37:47 | +1 m / −1 m |
| 38 km | 4:16 | 4:16 | 2:42:02 | +1 m / −1 m |
| 39 km | 4:16 | 4:16 | 2:46:18 | +1 m / −0 m |
| 40 km | 4:16 | 4:16 | 2:50:34 | +1 m / −0 m |
| 41 km | 4:16 | 4:16 | 2:54:51 | +1 m / −1 m |
| 42 km | 4:20 | 4:20 | 2:59:10 | +6 m / −1 m |
| Finish | 4:15 | 0:50 | 3:00:00 | +0 m / −1 m |
Race-morning weather
Air temperature and relative humidity by hour from the first wave’s 08:20 start, from 101 mornings within three days of the race date since 2011 at KYOTO, JA. Cool and warm are about the 10th and 90th percentile mornings by heat stress. Median wind 9 km/h.
Held on the second Sunday of March, with an 08:20 start. The nearest usable station is Kyoto, about 11 km west of the start.
| Local time | Cool | Typical | Warm |
|---|---|---|---|
| 08:20 | 2°C · 67% | 6°C · 67% | 11°C · 78% |
| 09:20 | 4°C · 55% | 7°C · 62% | 13°C · 67% |
| 10:20 | 6°C · 53% | 9°C · 47% | 16°C · 50% |
| 11:20 | 7°C · 48% | 10°C · 49% | 17°C · 47% |
| 12:20 | 7°C · 57% | 12°C · 37% | 19°C · 42% |
| 13:20 | 7°C · 55% | 12°C · 39% | 18°C · 44% |
| 14:20 | 7°C · 57% | 12°C · 44% | 20°C · 39% |
| Date | Start | +3 hours | Peak WBGT |
|---|---|---|---|
| 2025-03-09 | 3°C · 80% | 10°C · 44% | 12°C |
| 2024-03-10 | 2°C · 78% | 8°C · 39% | 10°C |
| 2023-03-12 | 13°C · 71% | 21°C · 53% | 21°C |
Data & method
- Route: Strava route export of the 2025 Biwako Marathon (user-supplied GPX, 42.35 km), Ojiyama Stadium to Karasuma Peninsula; third-party reference geometry, not an organizer-published route. Measured at 42.35 km and scaled to 42.195 km.
- Elevation: Copernicus GLO-30 DEM (30 m), © DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018, provided under COPERNICUS by the European Union and ESA. Sampled every 25–50 m, with bridges set to deck height and smoothed over 200–400 m.
- Weather: hourly observations from NOAA’s Integrated Surface Database (station 47759099999).
- Small climbs on flat courses can be terrain-model noise; they add only seconds to the estimates.
- This reference GPX has not been verified against the current edition. Check the organizer's latest course map before using its pacing plan.
Frequently asked questions
Is the Biwako Marathon hilly?
The course climbs about 42 m (138 ft) and descends about 38 m in total, which is flat. At even effort the terrain alone changes a 3:00 flat-course marathon by +0:17 and a 4:00 by +0:22.
What flat-course time do I need to break 3 hours at the Biwako Marathon?
About 2:59:43 on a flat course, assuming a typical race morning. For a sub-4 you need about 3:59:38. Switch the weather off in the calculator to see the terrain-only figure.
What is the weather usually like at the Biwako Marathon?
On a typical race morning it is about 6°C (43°F) at the first wave’s start and 10°C (50°F) three hours later, with a dew point near 0°C. That costs a 3-hour runner about 0:00 and a 4-hour runner about 0:00. Figures come from airport observations within three days of the race date since 2011.
How is the course-adjusted time calculated?
The course is cut into 100 m pieces. Each piece is run at your flat-course pace times a grade factor (about +3.3% per 1% uphill and −1.8% per 1% downhill) and a heat factor from shade WBGT at the time you reach it. Adding the pieces gives the course time, and the calculator works backwards from a goal the same way.