The 11 100K ultramarathons in Japan, with each one's climb, cutoff and date. Every race links to its own page, where you can see how it fits the runner you are now.
| Race | Distance | Where | Date | Climb | Cutoff |
|---|---|---|---|---|---|
| River Shimanto | 100km | Shimanto, Japan | Oct 18, 2026 | 2,297 ft | 14 h |
| OSJ Kami 100 | 101km | Hyogo Pref., Japan | Oct 31, 2026 | 17,418 ft | 25 h |
| Tokyo 100 | 100km | Tokyo, Japan | Nov 7, 2026 | 23,002 ft | 30 h |
| GGR Ishikiriba | 100km | Kitahiroshima, Japan | Feb 21, 2027 | 26,047 ft | 15 h |
| Hiroshima Trail | 100km | Hiroshima, Japan | Apr 10, 2027 | 20,945 ft | 32 h |
| Yatsugatake Nobeyama | 100km | Nobeyama, Japan | May 16, 2027 | 6,562 ft | 14 h |
| Tamba 100 Adventure Trail | 103km | Tamba, Japan | May 29, 2027 | 13,123 ft | 43 h |
| Okushinano 100 | 100km | Nagano Pref., Japan | Jun 5, 2027 | 15,354 ft | 21 h |
| Hida Takayama 100 km Ultramarathon | 100km | Takayama, Japan | Jun 13, 2027 | 3,937 ft | 14 h |
| OSJ Ontake 100km Ultra Trail | 99.5km | Otaki, Japan | Jul 18, 2027 | 11,138 ft | 20 h |
| Tango 100 km Ultramarathon | 100km | Kyotango, Japan | Sep 19, 2027 | 4,548 ft | 14 h |