
Photo: Norio NAKAYAMA · CC BY-SA 2.0 · Wikimedia Commons
Nagashima Onsen is a hot spring town in Mie, Japan. The water leaves the ground at 60°C, hot. Officially the water is classed as simple spring, chloride spring and bicarbonate 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.
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Smooth, slightly slippery water. Often nicknamed bihada-no-yu, the water for beautiful skin.
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.