Amagase Onsen Yakushi-yu open-air communal bath
Amagase Onsen, where steam rises along the Kusu River in Hita, Ōita, is counted with Beppu and Yufuin among the 'three great springs of Bungo'. Its trademark is the communal open-air baths dotted along the riverbed, and Yakushi-yu is one of the most approachable: a single rock tub, mixed bathing, ¥100 dropped into an unattended box. The 75°C simple sulphur spring is diluted to a comfortable temperature, with a faint whiff of sulphur and a view of the spa street across the river. Open 10:00–22:00 daily; wrapping a bath towel is allowed, which makes it easy for first-timers, and it is lit and atmospheric at night. Stroll the town, rebuilt after the 2020 floods, and try the other riverside baths such as Kanda-yu and Ekimae Onsen. About 10 minutes on foot from JR Amagase Station.