In the hot-spring heaven that is Japan, there are a countless number of onsen from Hokkaido to Okinawa, from those of luxurious spas in nondescript concrete buildings to rotenburo set in pristine natural surroundings.
Obviously what lures millions of onsen bathers back again and again is that wonderful feeling of just being able to close your eyes and forget about life's daily hassles -- the boss, the crowds, the headaches. The relaxation effect of onsen, however, is just the tip of the iceberg.
"Onsen therapy has various medical effects," says Yuko Agishi, a 71-year-old physician and honorary professor at Hokkaido University. "It is a type of alternative or complementary medicine, not directly curing the cause of the disease but treating the body as a whole; assisting in recuperation, rehabilitation and disease prevention."