熊入温泉 is a hot spring town in Kumamoto, Japan. The water leaves the ground at 36–45°C, hot. Officially the water is classed as simple spring.
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.
33.0216, 130.6856 — open the map
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