Do you like very hot baths? If so, you'll love Kusatsu Onsen Town in Gunma Prefecture. The water bubbles from the ground at about 52 degrees - much too hot for bathing. Passing through Yubatake (hot water field) cools the water enough to fill the many bath houses around town. I visited two of the free public bath houses, but the temperature of the water was around 45 degrees - still too hot for me. I couldn't even last 5 minutes! The foot bath I tried was about the same temperature too, but was easier to bear because only my feet were immersed.
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