Shimanto River Ultra Marathon Online Challenge Japan 2026: November 100K

Shimanto River's November online challenge offers a month of running on participants' own routes, inspired by the Kochi ultramarathon. It is organised by R-bies Sports Foundation and operated by R-bies. This listing is for the separately entered November one-month challenge, not the physical river race, the December round or a multi-month package.

Build the total across November

Accumulate at least 100 km between 1 and 30 November 2026. Multiple sessions count towards the total; a continuous 100 km ultramarathon is not required.

Record activity with TATTA, using the same RUNNET account as the registration. Only Running and Trail Run activities qualify. Walking, Hiking and Cycling are excluded, and manual distance entry is generally not accepted. Connect any compatible GPS watch before starting and check that the event appears in TATTA after payment is confirmed.

Synchronise eligible recordings into TATTA within the event period. Activities crossing from 31 October into 1 November, or from 30 November into 1 December, do not count. Test recording beforehand and leave time for synchronisation rather than relying on a last-minute upload. The registration instructions recommend keeping activity maps private or visible only to friends.

Entry conditions

Participants must reside in Japan and have a smartphone capable of using TATTA. No age limit is stated for the challenge, although RUNNET restricts payment methods for applicants under 18. Each participant must register using their own account; proxy family and group entry are unavailable.

The four prices are alternative participant packages for the same running target. Some higher-priced packages offer a choice between clothing and local food, not every listed item together. Select the package, clothing colour and size carefully because the registration page says changes cannot be made after entry.

Practical checks

The medal is conditional on accepted completion. No completion certificate is advertised in RUNNET's event outline, and participant insurance is not included. This virtual entry does not provide access to the physical Shimanto race or its aid stations, venue and transport.

For this online challenge, contact tatta-campaign@runners.co.jp, identifying the November one-month category. Confirm any delivery or tracking question with that office rather than relying on instructions for a different R-bies event.