Sansuikan Kawayu Matsuya

Kawayu Onsen is the place where hot water wells up through the gravel of the Oto-gawa (大塔川) and people scoop themselves a bath out of the riverbed by hand. Matsuya sits right on that stretch, with its own source running untreated into the inn's bath, a sodium bicarbonate and chloride water you are told not to rinse off because it holds the heat. From December to the end of February the village dams part of the river into the Sennin-buro (仙人風呂), a huge open-air bath that is free to anyone and about seven minutes' walk away. Since December 2025 the inn has run separately from its sister property next door: no meals now, plain Western rooms and self check-in, which suits Kumano Kodo walkers who want a bed and a soak and not much else. Kumano Hongu Taisha is five minutes by car.