Jigokudani Yaen-kōen 地獄谷野猿公苑
The monkeys do not get in to wash as we do, but only when it is more than 10 degrees below zero.
Nature reserve in the volcanic gorge of Jigokudani (‘valley of hell’, from the steam rising from the ground), managed for observing wild Japanese macaques. Opened in 1964, it came about when a macaque happened to discover the outdoor bath of the nearby inn; for hygiene reasons a pool just for them was dug inside the park. Photos of the monkeys in the onsen made the cover of LIFE in 1970.
Nagano
Kanbayashi Onsen, Sunadome, Snow Monkey Park