Kawayu Onsen Sennin-buro River Bath

This giant open-air bath is created by damming the Ohtou River and letting the natural hot spring waters fill the pit. Because much depends on Mother Nature, the pool tends to be a different size every year. The water springs from the riverbed at a hot 73 degree but then mixes with the crystal clear waters of Ohtou River, bringing the temperature down to about 40 degree. The pool is enclosed along the perimeter by a reed screen, leaving the rest open to the skies and stars for you to enjoy while soaking in the warm waters.