Kaminoyama Onsen Shimo-Ōyu Public Bath
The oldest of the communal baths surviving in the spa town of Kaminoyama, a former castle and post town about 10 minutes on foot from Kaminoyama-Onsen Station on the Yamagata Shinkansen. Moved to its present site in 1624, it is said to have been used by the Zen master Takuan. The big tub is split into hot and tepid halves, filled free-flowing with clear sodium-calcium-chloride-sulphate water. With its flagstone washing area and old-style attendant's counter, it charges an astonishing ¥150 for adults and ¥100 for children (hair washing ¥100 extra), and the tatami hall upstairs can be used for a day's rest for ¥300. Open 06:00–22:00 (from 06:30 December–February; last entry 21:30), every day. Take a morning or evening dip with locals while touring Kaminoyama Castle, the samurai-house street and the town's five foot baths. About 25 minutes by car from Yamagata city, 40 minutes from Zaō Onsen. No soap is provided, so bring your own; park in the shopping-street car park opposite.