A Finnish-style sauna that introduced the first auto-löyly in Yunokawa Onsen. The room makes luxurious use of domestic hinoki wood, and the calming woody aroma fills the air the moment you open the door. It uses a ZIEL sauna stove designed to deliver high-quality löyly, along with the finest artificial stone, Kerkes Stone. With rich humidity and waves of heat from the auto-löyly that occurs about once every 20 minutes, you can enjoy deeply refreshing sweating from the core of your body.

An open-air outdoor cold plunge bath attached to the large public bath, and the only one of its kind in the Hakodate area. Its appeal lies in being able to cool down your body, heated all the way through by the sauna, while looking up at the open sky. The water temperature changes depending on the season and period, so you can enjoy a different level of briskness from spring through winter. In the nearby outdoor air-bathing space, totonou chairs (garden chairs) are provided, allowing you to feel Hokkaido's refreshing breeze and relax deeply.