
Photo: Mamusi Taka · CC BY-SA 3.0 · Wikimedia Commons
Hyakuana Onsen is a hot spring town in Saitama, Japan. The water leaves the ground at 9°C, cool enough that the baths here are usually reheated.
The water type for this town has not been identified yet. It is on the list to check.
Figures from the town's Japanese Wikipedia article.
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.