Hoteiya

Hoteiya (ほてい屋) is a small, family-run ryokan in Semi Onsen. The baths are indoor only, one for men and one for women, and they swap in the evening, so a stay gives you both. Guests describe the water as leaving the skin smooth. Some Japanese-style rooms look out on the river. The public bath next door runs hotter, about a minute's walk away, if you want more heat.