
Photo: Kiyonobu Ito · CC BY 2.0 · Wikimedia Commons
寿都温泉 is a hot spring town in Hokkaido, Japan. The water leaves the ground at 48°C, hot. It measures pH 7.2–8.8 — close to neutral. Officially the water is classed as chloride spring. Its sources put out around 204 litres a minute.
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Figures from the town's Japanese Wikipedia article.
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