Kawayu, Hongu-cho, Tanabe City, Wakayama Prefecture
Rating
Cost per person
Free
Sennin-buro Hot Spring is a unique, seasonal outdoor onsen located in Kawayu Onsen, Wakayama. From December to February, the Oto River transforms into a large, free-to-enter hot spring. Visitors can dig their own personal bath in the riverbed where hot spring water bubbles up. Note that the river's water level can fluctuate, sometimes submerging the onsen entirely. It's recommended to wear swimwear as it is a mixed-gender bathing area. A free changing room is available across the road. Be prepared to walk a short distance on the riverbank in your swimwear.