Tsukubarenzan trailrun in ISHIOKA 70 km 2026
Starts and finishes at the Yasato branch office in Ishioka, Ibaraki. The first part is on roads through the old Yasato district, past thatched farmhouses and gatehouses, and the second part is trail over the mountains of the Tsukuba range. In the 70km, the first ~36km is road, then the trail runs through mountains shared by Ishioka, Kasama and Sakuragawa.
The course tops out at 709 m (low point 19 m). There are 2 big climbs: 512 m around 24–42 km; 638 m around 50–59 km. About 50% of the distance is gentle (under 5% grade). In 2025, 75% of starters finished. The median finish was about 11 h.
Estimate your finish from your ITRA index
Estimate (no finisher data for this race)
Enter your ITRA performance index to get an estimated finish time, aid-station splits and cutoff margins. This race has no finisher ITRA data, so it uses the transfer model: your predictions for the 205 races that do have finisher data, scaled by distance and elevation gain (km-effort) — the same calculation as the TRAIL STATUS app. Nothing is saved or sent.
The app adds predictions from your training log (Strava), race-day pacing and more. Free, no sign-up.
Predict in detail from my Strava trainingOverview
- Date
- Sun, 27 Sep 2026
- Start
- 05:00
- Location
- Ibaraki, Japan
- Distance
- 70 km
- Elevation gain
- 2,460 m
- Time limit
- 13h
- ITRA
- 50M
- Official website
- tukubarenzantrail.teamsportsjapan.jp/course
Elevation profile
Aid stations and cutoffs
| # | Distance | Aid station | Segment | Cutoff |
|---|---|---|---|---|
| 1 | 36 km | Aid 1第一関門（シューズ交換所） | 36 km | Day 1 11:006h |
| 2 | 44 km | Aid 2第二関門 旧洗心館 | 8 km | Day 1 13:308h 30m |
| 3 | 53 km | Aid 3第三関門 木植コミュニティセンター前 | 9 km | Day 1 14:009h |
| 4 | 60 km | Aid 4第四関門 一本杉峠 | 7 km | Day 1 15:0010h |
| F | 70 km | FinishFINISH 石岡市八郷支所 | 10 km | Day 1 18:0013h |
The small figure under each cutoff is the time from the start. Day 1 is the day of the start.
2025 results
187 starters, 140 finishers (74.9% finish rate). Finish times of those who finished:
- Fastest
- 7h 8m
- Top 10%
- 8h 52m
- Top 25%
- 9h 49m
- Median
- 10h 49m
- Top 75%
- 11h 39m
- Top 90%
- 12h 9m
- Last finisher
- 12h 38m
"Top 25%" means one in four finishers had crossed the line by this time.
Years with a different course or different cutoffs are not directly comparable.
Practice courses
See the course on the Runnable map ↗
Runnable has practice courses on this race's trails, split into sections to run and sections to walk (pages in Japanese).
- Runnable practice course (70.9 km)
Other races
- OSJ Okukuji Trail 59 km 2025Sun, 25 May 2025 · Ibaraki, Japan · 59 km
- OSJ Okukuji Trail Short 32.5 km 2025Sun, 25 May 2025 · Ibaraki, Japan · 32.5 km
- Tsukubarenzan Middle 45 km 2026Sun, 27 Sep 2026 · Ibaraki, Japan · 45 km
- Tsukubarenzan Short 25 km 2026Sun, 27 Sep 2026 · Ibaraki, Japan · 25 km
- BULSS 茨城 (Backyard Ultra Last Samurai Standing) 2026Sat, 7 Nov 2026 · Ibaraki, Japan
- Joshu Hotakasan Skyview Trail 77km 2026Sat, 12 Sep 2026 · Gunma, Japan · 77.5 km
From your training log, TRAIL STATUS estimates your finish time, aid-station splits and cutoff margins for this race.
Predict my raceCompiled from each race's official information. Details can change, so always check the race's official website for the latest. Spotted a mistake? Please tell us through the contact form.
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