
Photo: Totti · CC BY-SA 4.0 · Wikimedia Commons
寒の地獄温泉 is a hot spring town in Oita, Japan. The water leaves the ground at 14°C, cool enough that the baths here are usually reheated. Officially the water is classed as sulfur spring. Its sources put out around 2,160 litres a minute.
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.
33.1135, 131.2271 — open the map
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.