Spas with groups in Japan

Dogo Onsen, Ehime

A roughly 3,000-year-old public hot spring bathhouse in Matsuyama, designated an Important Cultural Property, open daily with walk-in day passes from 700 yen.

Shibu Onsen, Nagano

Reservation-only private hot spring and sauna suites at a Nagano brewery complex, built around a craft beer bathing plan for two to four guests.