An authentic Finnish-style sauna that introduced self-löyly for the first time in Noboribetsu Onsen. The walls and benches are luxuriously finished with Japanese cypress and white birch, filling the room with a rich, refreshing woody aroma the moment you enter. Pouring water over the sauna stones releases steam rich in negative ions, gently raising the perceived temperature and creating a comfortable, effortless sweating experience.

A very rare hot spring district first: a cold plunge bath made from Noboribetsu Onsen’s signature milky sulfur spring source, cooled with a chiller to around 17 to 19 degrees. The water is milky-white and carries a faint sulfur aroma, with a flow-through setup. After sauna use, you can slowly and gently cool down while being enveloped in the smooth minerals unique to the source spring, for a truly sublime experience.

A natural cold bath using underground water from the clear Kusurisambetsu River, whose name comes from the Ainu language. Without a chiller, the natural water is kept at around 13 to 15 degrees and offers a crisp, refreshing coolness that rapidly chills the body as it sinks into the skin. You can enjoy a luxurious alternating bath experience with the milky-white Gensen Cold Plunge Bath, which differs in both temperature and spring quality.