世知原温泉 is a hot spring town in Nagasaki, Japan. The water leaves the ground at 37.4°C, comfortably warm. It measures pH 8.3 — mildly alkaline, the slippery kind. Officially the water is classed as bicarbonate spring. 1 inns take visitors here.
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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