As amusement and theme parks nationwide struggle to attract visitors, operators in Tokyo are digging deep to tap one of Japan's favorite past times and lure a wider range of patrons.

On May 1, an amusement facility featuring an "onsen," or hot spring, bubbles into action in central Tokyo, the second such facility to open here since March. A third kicks off in June.

While the specific concept differs with each facility, they all promote the "iyashi," or healing, functions of onsen. Operators are hoping this will help attract more adults than regular amusement parks.