
Photo: Totti · CC BY-SA 4.0 · Wikimedia Commons
Kutsuno Onsen is a hot spring town in Nagano, Japan. The water leaves the ground at 75°C, hot. Officially the water is classed as simple spring, chloride spring, sulfate spring and sulfur spring. 5 inns take visitors here.
Mild and low in dissolved minerals. Usually clear and gentle on the skin, which is why these baths are often recommended for first-timers.
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Clear water with a faintly bitter taste. Known for holding heat.
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.
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.