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湯ノ岱温泉 is a hot spring town in Hokkaido, Japan. The water leaves the ground at 32–39°C, comfortably warm. It measures pH 6.4–6.8 — close to neutral. Officially the water is classed as bicarbonate spring.
Smooth, slightly slippery water. Often nicknamed bihada-no-yu, the water for beautiful skin.
Figures from the town's Japanese Wikipedia article.
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.