A genuine dry sauna in authentic Finnish style, located next to the large bath. This compact room, lit with calm indirect lighting, features a sauna-stone convection stove and allows self-löyly. When löyly is poured, soft heat and the aroma of birch instantly fill the room, encouraging comfortable, thorough sweating without putting undue strain on the body. From the windows, you can look out over Lake Shikotsu and the vast primeval forest of the national park, enjoying a luxurious moment of meditation.

A luxurious cold plunge bath set in one corner of the open-air bath with a scenic view, using free-flowing cold water from Lake Shikotsu. The water drawn from the same source as Lake Shikotsu's pristine natural water, which has repeatedly been ranked Japan's best for water quality, is exceptionally clear and wonderfully smooth against the skin. After a hot sauna session, slipping into it instantly envelops your body in a mellow coolness and delivers outstanding refreshment. Right in front of the cold plunge bath stretches Lake Shikotsu in the national park, promising an exquisite outdoor air bathing experience.