Nishiyama Onsen Ryokan Nakanoyu

This streamside ryokan in the Aizu Nishiyama Onsen (会津西山温泉) area sits on three private springs, Nakanoyu, Sugino-yu, and Arayu, each with its own character. The water has a faint sulfur scent, a slightly thick feel, and mineral flakes that drift through the bath; reviewers describe it as the kind of soak that makes your whole body go limp. The building has a quietly historical feel, clean and worn in equal measure, and the mountain-inn food is what you'd hope for.