The Japanese macaque (Macaca fuscata) — known colloquially as the snow monkey — is the world’s most northerly non-human primate and one of Japan’s most iconic wildlife subjects. The image of a macaque sitting serenely in a steam-wreathed hot spring pool surrounded by snow has become one of the country’s defining photographs. The Jigokudani Monkey Park in Nagano Prefecture, where this behaviour was first documented, remains the most accessible site for observing it, but wild macaque populations exist across Japan from Yakushima to the Shimokita Peninsula.
Jigokudani Monkey Park, Nagano
Jigokudani — “Hell’s Valley” — is a steep-sided gorge in the Shiga Kogen highlands of Nagano Prefecture, named for the boiling water and steam that vent from the ground. A troop of approximately 160 wild Japanese macaques has used a purpose-built outdoor hot spring pool (installed in 1967) as a bathing site, and observation of this behaviour has attracted visitors for over 50 years.
The monkeys are not fed or managed — they come and go freely. Bathing behaviour peaks in winter (December to March) when temperatures drop below freezing and the warm pool provides thermoregulatory benefit. In summer, the same troop frequents the forest above the valley but rarely uses the pool. The most atmospheric visits are during snowfall or immediately after, when the contrast between white landscape and steaming water is at its sharpest.
Access: The park is reached by a 30-minute walk from Kanbayashi Onsen bus stop. Buses run from Yudanaka Station, which is accessible from Nagano City by Nagano Dentetsu railway (approximately 40 minutes). The walk is through forest on a clear path and is manageable in winter conditions. Entry fee applies; no feeding or touching of monkeys is permitted.
Macaque Behaviour and Biology
Japanese macaques live in troops of 20-100 individuals, organised around matrilineal hierarchies. The hot spring bathing behaviour at Jigokudani appears to have originated with a single young female in 1963 and was culturally transmitted within the troop — an early documented case of social learning in non-human primates that attracted significant scientific attention. Not all troop members bathe; individual variation and rank influence access to the pool.
Macaques are omnivores, eating leaves, bark, insects, and — in coastal populations — shellfish and seaweed. Winter diet consists largely of bark and whatever stored food individuals can locate under snow. The Yakushima macaque population (on Yakushima island in Kagoshima) is notable for the unusually dense forest environment and for sharing territory with Yakushima deer in what appears to be a loosely mutualistic relationship.
Other Macaque Viewing Locations
- Arashiyama Monkey Park Iwatayama, Kyoto: A hillside park above Arashiyama where a troop of approximately 120 macaques lives semi-wild. An indoor feeding station allows close observation; the hilltop provides excellent views over Kyoto. The monkeys are not in hot springs — this is a straightforward wild troop observation site accessible from central Kyoto.
- Takasakiyama Natural Zoological Garden, Oita: The largest wild macaque troop accessible to the public in Japan — approximately 1,300 individuals in multiple sub-troops. Feeding stations create predictable gathering opportunities. Located near Beppu.
- Yakushima Island: The most naturalistic observation context — macaques encountered on forest hiking trails without management or feeding. Requires standard hiking preparation.
For visitors combining Jigokudani with broader Nagano travel, the park pairs naturally with visits to Hakuba ski resorts in winter and Japan wildlife watching throughout the year.