
Photo: 運動会プロテインパワー · CC BY-SA 4.0 · Wikimedia Commons
Kasagata Onsen Seseragi no Yu is a hot spring town in Hyogo, Japan. The water leaves the ground at 28.6°C, cool enough that the baths here are usually reheated. It measures pH 8.92 — mildly alkaline, the slippery kind. 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.
35.0232, 134.8207 — open the map
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.