
Photo: SpringField1967 · CC BY-SA 3.0 · Wikimedia Commons
Tengu Hot spa is a hot spring town in Nagano, Japan. The water leaves the ground at 9°C, cool enough that the baths here are usually reheated. It measures pH 5.8 — mildly acidic. Officially the water is classed as iron spring. 1 inns take visitors here.
Turns reddish brown as the iron meets air. The water is clear at the source.
Figures from the town's Japanese Wikipedia article.
36.3802, 138.4789 — open the map
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