Oki Bull Sumo (Ushi-tsuki) is said to have been introduced by Emperor Gotoba who was exiled to the Oki Islands in 1221 after having been defeated in the Jokyu Rebellion. It is said that the emperor was pleased when he saw small cows butting heads.
- First Annual Tournament (2nd week January, Oki Momo Dome)
- Spring Tournament (May 4, Oki Momo Dome)
- Summer Tournament (August 15, Oki Momo Dome)
- Hassaku Tournament (September 1, Sayama Bull Sumo Ring)
- Ichiyagadake Tournament (October 13, Ichiyagadake Bull Sumo Ring)
- Kaminishi Shrine Autumn Tournament (November 13, Kaminishi Shrine Bull Sumo Ring )
* During peak tourist season Bull Sumo displays are held at the Momo Dome (next to Oki Kokubunji Temple). Contact the Oki Islands Tourism Association for further information.
Bull Sumo still takes place on Dōgo Island today. It is a non-commercial event that has been maintained in Oki as a local entertainment for hundreds of years. A unique feature of Oki Bull Sumo is that the ‘tsunatori’, or ‘rope holder’ of each bull must stay in the ring holding the rope of their bull throughout the entire match.