TATTA CHALLENGE 100K 2026
Also known as: Tatta Challenge · tatta · Trail Run Boys
A grassroots 100 km on Mt. Tatsuda, just north of central Kumamoto city: ten laps of a roughly 10.6 km cross-country-style trail loop from the Tatsuda-yama Ikoi-no-Mori park, with about 400 m of climbing per lap and a 14.5-hour limit (no new lap after 19:20). You pass the venue every lap, so you can run your own aid. Organised by the local running group Trail Run Boys; entry is by lottery.
The course tops out at 155 m (low point 46 m). About 80% of the distance is gentle (under 5% grade), so there is a lot of running.
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 287 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.
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Predict in detail from my Strava trainingOverview
- Date
- Sun, 11 Oct 2026
- Start
- 06:30
- Location
- Kumamoto, Japan
- Distance
- 106 km
- Elevation gain
- 4,000 m
- Time limit
- 14h 30m
- ITRA
- 100K
Elevation profile
Aid stations and cutoffs
| # | Distance | Aid station | Segment | Cutoff |
|---|---|---|---|---|
| 1 | 10.6 km | Aid 11周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 2 | 21.2 km | Aid 22周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 3 | 31.8 km | Aid 33周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 4 | 42.4 km | Aid 44周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 5 | 53 km | Aid 55周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 6 | 63.6 km | Aid 66周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 7 | 74.2 km | Aid 77周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 8 | 84.8 km | Aid 88周目終了 立田山憩の森（エイド） | 10.6 km | — |
| 9 | 95.4 km | Aid 99周目終了 立田山憩の森（エイド） | 10.6 km | 19:2012h 50m |
| F | 106 km | FinishFINISH 立田山憩の森 | 10.6 km | 21:0014h 30m |
The small figure under each cutoff is the time from the start.
Registration
- Registration
- Sat, 27 Jun 2026 – Fri, 10 Jul 2026
- Entry
- Lottery
- Lottery results
- Sun, 19 Jul 2026
Add the race in the app to put registration opening and closing and the lottery results into your calendar.
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- SWAN AND WOLF 70K 2026Sat, 14 Nov 2026 · Kumamoto, Japan · 70 km
- Minami Aso Caldera Trail 50 km 2026Sat, 19 Dec 2026 · Kumamoto, Japan · 50 km
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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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