有明海
The Kashima Gatalympics is an event held in the mudflats of the Ariake Sea off Kashima city in Saga Prefecture, Japan. The event takes place every year at the end of May. Participants compete in novelty games such as the mud sumo tournament, the 25m dash and the surf board race. The Ariake Sea has a tidal range of six metres, which on a low tide, exposes the mudflats on which the games take place. It has become a well known event throughout the Saga Prefecture with around 300 athletes participating each year.