Gokan no Yu Tsuruya

Tsuruya stands across the road from the Zao Onsen bus terminal at the foot of Takayu-dori, so you step off the bus from Yamagata and walk straight in. The inn's own spring rises on site without a pump at about 200 litres a minute and 55.5 °C, and every bath uses it with no added water or heat. The inn says the water's pH of 1.5 ranks second in Japan for acidity.

The two main baths each have an outdoor tub and stay open around the clock, apart from about two hours of cleaning from 9:30. Four private baths line a corridor called Yuraku-dori, and online bookings get one 50-minute session free, then ¥1,100 for each extra one. Breakfast and dinner come in your room or a private dining room, with a Yamagata set menu or a Zao beef main as sukiyaki, shabu-shabu or steak.

Rooms mix ten-tatami Japanese rooms, Japanese-Western rooms with twin beds and new-style rooms renewed in 2024 on the sixth floor and up. Some have a bath that runs on ordinary water, and others have only a toilet and basin, so ask for a bath when you book. In winter a free shuttle runs on a timetable to three of the slopes, and a changing room by the front desk lets skiers get out of their gear before check-in.