Lake Saroma 100K Online Challenge Japan 2026: Year-end 1-Month

Lake Saroma's Year-end 1-Month Online Challenge is a distinct December-only virtual 100 km round from the November 1-Month and November-December Stage 2 challenges already listed in ARC.

Accumulate 100 km during December

Complete at least 100 km between 1 and 31 December 2026 using the TATTA GPS app. Multiple activities may be combined during the challenge period.

Participants must register using their own RUNNET account and be able to record eligible activity through TATTA. Japan residency is required. No age restriction is published.

Registration and packages

Registration closes on 26 November 2026 at 23:59 JST, or earlier if capacity is reached. Four package prices are published: JPY4,990, JPY6,990, JPY8,990 and JPY12,990, with RUNNET handling of 6% because each package exceeds JPY4,000.

All packages include original Lake Saroma participation apparel, with the organiser listing a T-shirt or sleeveless option, and verified finishers receive a finisher medal. Higher-priced package extras vary and should be confirmed on the official Saroma page before payment.

Important limitations

This virtual challenge does not count toward Saroman Blue qualification. Participant insurance is not included by the organiser; entrants should arrange their own coverage.

Credibility

The challenge is published directly on RUNNET and the official R-bies Sports Foundation Saroma online site. R-bies Sports Foundation is the named organiser, providing a strong institutional and registration chain.