Jōshin’etsu-kōgen National Park is a national park in the region of Chūbu in Japan. The park on the main island of Japan, Honshū, is spans across the prefectures Gunma, Nagano, and Niigata and has several active and dormant volcanoes on its territory.
Inside the national park, in the valley of the Yokoyu-River, is the Jigokudani Monkey Park (地獄谷野猿公苑, Jigokudani Yaen Kōen) located. The name of the park comes from a large population of wild Japanese macaques, who retreat to the valley in winter.
A highlight for visitors is swimming in the warm waters of the onsen (Hotsprings). Especially at warm temperatures and without snow the monkeys do without a warming bath.
