Photo: Sakaori (talk) · CC BY 3.0 · Wikimedia Commons
Itō Onsen is a hot spring town in Shizuoka, Japan. Officially the water is classed as simple spring and chloride spring. Its sources put out around 34,000 litres a minute.
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.
Figures from the town's Japanese Wikipedia article.
34.9904, 139.0840 — open the map
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.