桑田山温泉 is a hot spring town in Kochi, Japan. The water leaves the ground at 18.3°C, cool enough that the baths here are usually reheated. It measures pH 9.5 — strongly alkaline. Officially the water is classed as sulfur spring. Its sources put out around 360 litres a minute. 1 inns take visitors here.
The classic rotten-egg smell and milky white water. It can tarnish silver jewellery, so take it off.
Figures from the town's Japanese Wikipedia article.
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