A quiet large bath surrounded by abundant nature, available only to guests staying at Kashoutei and Sanso. It has an indoor bath and an attached open-air bath, and the water is luxuriously fed by a fresh natural source with absolutely no added water or reheating. You can feel the changing seasons of Shima with your whole body, from the fresh green of spring, the refreshing summer breeze, the brilliant autumn leaves, to the solemn snowy scenery of winter, while enjoying a blissful forest bathing experience listening to the murmuring river and birdsong.

Built in 1930, this bathhouse is a registered Tangible Cultural Property that retains the refined atmosphere of Taisho romance and is widely regarded as one of the most beautiful in Japan. Beautiful light filtering through the high ceiling and arched windows gently envelops the bath area. Five historic stone bathtubs set into the floor are generously filled with the abundant self-springing waters of Shima Onsen, allowing you to savor a luxurious and auspicious bathing journey while feeling the differences in water temperature and reflecting on the bathing culture of that era.

A charming private, lockable reserved bath that can be used free of charge by guests staying at Kashoutei and Sanso. Two atmospheric indoor baths, “Seki” and “Zen,” are available, and no advance reservation is required. If it is vacant, you can lock the door from the inside and bathe as many times as you like in complete privacy. It is also filled with fresh 100% free-flowing natural hot spring water, so you can enjoy a soothing soak and quiet conversation with someone special without any reservations.