Shimizu Onsen (Rekishi Roman no Yu)

Shimizu Onsen sits high up the Arida river valley, in the hill country south of Mount Koya that people here call Ura-Koya (裏高野): the back side of the mountain, crossed by the old roads pilgrims took to Koyasan. The bath was rebuilt on the plot next door and reopened in 2024, warm local timber throughout, and the main tub faces a wall of window with nothing behind it but forest, so the green lies on the water like a painting. The spring rises from about 400 metres down, weakly alkaline sodium chloride and bicarbonate, and it comes up cold, so beside the heated bath there is a plunge fed straight from the source and a mist sauna: going back and forth between the two is rather the point here. Locals call it a bijin-no-yu (美人の湯) for how smooth it leaves the skin. Afterwards, a timber-lined rest space with mikan juice and Aridagawa cider from the valley.