Stone Spa
Around three hundred years ago in Edo era Japan, Locals found that some injured animals lying on the rock near by the Tamagawa hot spring, Akita County. Magically, the wound were quickly healed.
Therefore, people build similar Tamagawa rock bath (Stone spa) in the city so that everyone can enjoy it. This is the origin of famous "Stone spa energy room".
Stone spa 40 minutes equals to jogging 30 km.