Odaira Onsen Takimiya

Odaira Onsen Takimiya draws sulfur-spring water from two separate sources: an indoor bath that looks out at Kaen-no-taki (火焔の滝), a noted waterfall just above the inn, which is where the inn's name comes from ('Takimiya' / 滝見屋 literally means 'the waterfall-viewing house'), and open-air baths along a mountain stream, split by gender plus two more set aside for private, reservation-only use. The water runs clear with fine white flakes, faintly sulfurous and smooth on the skin. This is a remote mountain ryokan: the access road is steep and narrow enough that meeting an oncoming car is a real problem, and from the designated parking lot it's a good twenty-minute walk down to the inn, with an equally hard climb back up (a shuttle from Yonezawa station is available if you'd rather not drive it yourself). There's no cell signal, and nothing to do after dark but listen to the river. The inn went through a rough stretch a few years back that nearly closed it for good, but it pulled through and is open and running again.