Photo: Hyolee2 · CC BY-SA 3.0 · Wikimedia Commons
湯の児温泉 is a hot spring town in Kumamoto, Japan. Officially the water is classed as chloride spring and bicarbonate spring.
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Smooth, slightly slippery water. Often nicknamed bihada-no-yu, the water for beautiful skin.
Figures from the town's Japanese Wikipedia article.
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