Fujisan Ryokan
Namari's most famous ryokan (and its most famous onsen) is a dark wood house made of Japanese zelkova trees that is starting to show its age but still seems to have stories to tell, with rustic rooms without private baths in the main building and newer rooms with private baths in a concrete annex. The main reason to stay here is to have the opportunity to steep in the venerable Namari Onsen, which has a high ceiling and a round shape that resembles nothing so much as a giant inkwell. It is not the only hot spring available to you (and the water in the hot springs can be hot to the uninitiated), but the outdoor baths along the river are more milky. Relatively rare in these modern times, the ryokan has mixed-sex bathing with some hours reserved solely for women or men depending on the bath. Although the rooms in the main building have no private toilet, many find them nicer and more atmospheric than those in the newer annex, where the rooms do have private baths; the corner rooms overlooking a waterfall are particularly roomy and tastefully furnished. You can also use their bath for ¥800 per person without staying, and rent a towel for a few hundred yen extra.