Hot springs in Gero

Gero Onsen sits along the Hida River in Gifu Prefecture and holds a place among Japan's three great hot springs, sharing that distinction with Arima and Kusatsu. The ranking traces back to the Muromachi-period monk Banri Shukyu, whose writings first established it, and Edo-period scholars later affirmed the designation. The spring is a sodium bicarbonate source with a pH of 9.2, and bathers commonly describe the water as smooth and silky against the skin.