鳴き砂温泉 is a hot spring town in Kyoto, Japan. The water leaves the ground at 48.7°C, hot. Officially the water is classed as simple spring. Its sources put out around 507 litres a minute. 7 inns take visitors here.
Mild and low in dissolved minerals. Usually clear and gentle on the skin, which is why these baths are often recommended for first-timers.
Figures from the town's Japanese Wikipedia article.
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