白子温泉 is a hot spring town in Chiba, Japan. Officially the water is classed as chloride spring and iodine spring.
Salty water. The salt leaves a thin film on the skin, so you stay warm well after leaving the bath.
Contains iodine and often turns yellowish over time. Uncommon.
Planning a first soak? Read how an onsen stay works, and what to do if you have tattoos.