The rustic open-air bath "Hagakure no Yu" and the rock-style indoor bath "Komorebi no Yu." They are filled with milky-white hot spring water flowing directly from the source at 100%, boasting one of the highest acidity levels in Zao Onsen (pH 1.7). The sulfur-scented water is said to be a natural beauty serum, smoothing the skin and warming the body from the core. You can fully enjoy this famous hot spring while feeling the soft light filtering through the trees and the pleasant mountain breeze.

A heated bath tub located inside the large public bath, with the refreshing fragrance of Japanese cypress. It serves as a post-bath bath for those whose bodies have become tired from the strongly acidic hot spring, and it is also a gentle bath where people with sensitive skin or small children can warm up slowly and with peace of mind, even if they find acidic springs too stimulating.