This place is situated along the Machida River, at the outskirts of Hosenji Hot Spring Village. t is said that in the Kyoho era (1716 - 1735), a hunter who saw a deer bathing in a hot spring opened a path in the steep quay and opened a hot spring in the cave, and named the place where the hot spring was found as "Kabe-yu". The semi-cave mixed-gender bathing area that gives an impression of a roughly dug groove in the rocks produces abundant soft and silky hot spring water at a rate of 1,300 liters per minute. There is also a cave bath only for women. In the clear stream of the Machida River that flows right next to it, you can see the fireflies dancing in early summer.