Kakurean Hidaji

Every one of the ryokan's twelve rooms has its own open-air bath built from rock, plus a separate hinoki (檜) indoor tub, so you can soak any time without leaving the room. Two more open-air baths sit just outside by the river; they look out toward Mount Yakedake and can be reserved (kashikiri, 貸切) whenever they're free, no booking required. The water is clear and colorless, and locally it's known as Tenno-sen (天皇泉), the Emperor's Spring, tied to a legend that Emperor Murakami had it opened in the Heian period. Kakurean Hidaji sits in Fukuji Onsen, part of the Okuhida hot spring area at the foot of the Kita Alps, with only twelve rooms spread across a large property for privacy. It runs as a quiet, adults-only retreat: children of elementary-school age and younger aren't accepted as overnight guests. Meals are served fireside at an irori (囲炉裏) table for both dinner and breakfast.