Jigokudani Monkey Park Snow Monkeys at Jigokudani, Nagano

Jigokudani Monkey Park (地獄谷野猿公苑) is a park established to observe wild Japanese macaques in the Jigokudani Onsen area of Yamanouchi, Shimotakai District, Nagano Prefecture. Opened in 1964, the site is internationally known for macaques that enter a purpose-built outdoor hot spring in winter; English-language coverage often refers to the animals as “snow monkeys” or calls the area Snow Monkey Mountain.

Management and staff

The park is operated by the company Jigokudani Yaenkoen Co., Ltd., a subsidiary of the Nagaden Group. Its founding philosophy was to show coexistence between monkeys and people: the first director, Sogo Hara, opposed government-authorised culling and instead worked to feed troops upstream and reduce crop damage, a programme that led to the park’s formal opening on June 3, 1964. Park staff maintain long-term observation of the troop (staff have observed the macaques continuously since the 1980s) and oversee all feeding and visitor monitoring; the park emphasises that staff-only feeding and constant surveillance are central to safe, close observation.

Geography and climate

The park sits at the far end of the Jigokudani Onsen valley, on the Yokoyu River which rises in the Shiga Kogen area. The park lies at about 850 metres elevation. Heavy winter snow commonly exceeds one metre and winter minimums can fall below −10 °C. Immediately before the park entrance a hot spring fountain known as the Shibu Jigokudani geyser vents source water at nearly 100 °C, a reminder of the active geothermal environment that supplies the macaque bathing pool.

How the hot spring and bathing began

A playful young macaque first entered a human outdoor bath at the nearby Kourakukan ryokan, and adult monkeys soon copied it; for hygiene reasons the park later constructed a macaque-only outdoor pool. The pool measures about 4 m by 10 m. By the end of 2012 some 50–60 individuals typically used the pool between December and March. The water temperature in winter runs at roughly 42 °C—similar to what humans find comfortable—and the park interprets bathing as a behaviour to endure severe cold rather than a form of washing. Females and juveniles make up most bathers; dominant males rarely enter, a pattern the park attributes to males needing to stay ready to protect the troop and to their aversion to appearing smaller when wet. The park notes that bathing is only a small part of the macaques’ lives.

Biological notes from the Kyoto University Primate Research Institute explain why macaques do not suffer prolonged chill after bathing: their pelage has long, coarse outer hairs and short, soft underfur, and the long outer hairs repel water so that wetting does not leave the animals cold in the same way it would affect an animal with a different coat.

Origins and development

Post‑war logging reduced the monkeys’ upland food sources and troops moved down toward populated valleys, causing damage to apple orchards and other crops. Local residents requested control measures and the Forestry Agency issued a permit to shoot 50 animals. Sogo Hara resisted culling and—working over three years to win the trust of a wary troop—began targeted feeding upstream of the orchards (near the present Kourakukan). Feeding successes recorded by Nagano Electric Railway mountain staff around 1962 helped make the management approach feasible, and the park was opened in 1964 to present the concept of human–monkey coexistence to visitors.

The park later expanded local attractions; for example, a related garden attraction opened in 1979 under the same management umbrella.

Herd management, feeding and population control

Unlike many other monkey parks, Jigokudani does not sell food to visitors. The park’s feeding is carried out only by staff: feedings are scheduled at staff discretion, are irregular, and are not publicised. The stated rationale is that feeding is a management tool to stabilise observation conditions rather than entertainment; it is not presented as a show. Staff use modest, low‑calorie items such as barley with chaff, small raw soybeans, and apples as conditions require, because high‑value feeds risk obesity and disruption of natural behaviour.

In the 1990s the park introduced contraception as an individual population‑control measure; that program reduced birth rates where it was used. In favourable conditions the troop once numbered much higher (a figure cited for 1997 is about 360 animals). By the end of 2012 the main troop numbered roughly 160 individuals, of which about 50–60 were the typical winter bathers.

The feeding policy has attracted academic debate: in the late 1990s some researchers argued for a ban on provisioning for reasons including animal welfare and ecological disturbance, while other scholars responded that the park’s operation produced net benefits when weighed against its drawbacks.

Observing the monkeys, visitor patterns and getting there

The park sets strict rules for visitor conduct: feeding by visitors is strictly forbidden; visitors must not touch the monkeys, should keep their distance, must not stare into the animals’ eyes, should avoid over‑familiar behaviour, must not speak to the macaques to attract them, and must not use selfie sticks. The park explains that when visitors follow rules the macaques remain largely indifferent to human presence and visits proceed without incident; staff say that they constantly monitor visitors.

If the macaques are absent from the park, local authorities ask visitors to understand that the animals are likely out foraging in the surrounding mountains rather than “skipping” the park.

Access details recorded by the park: the nearest rail access is Yudanaka Station on the Nagano Electric Railway (Nagano Line); from there it is about a 10‑minute taxi ride to the park in normal conditions. In winter the access road is closed; visitors must walk a mountain trail of roughly 30 minutes from Kanbayashi Onsen. On winter weekends and the year‑end/New Year period a reservation bus that links Jigokudani, Shibu Onsen and Yudanaka Station operates limited services (reported as 5.5 round trips per day in the winter period); alighting at the Jigokudani bus stop places the park about a 10‑minute walk away. A combined park‑entry and round‑trip bus ticket is offered when the shuttle runs.

The park receives significant attention from media and photographers: press coverage since the late 1990s (helped by nearby Olympic facilities in 1998) lifted international awareness, and prizewinning photographs of the winter‑bathing macaques have appeared in international contests. Annual visitation is about 100,000 people overall; roughly 20% of visitors are from outside Japan, rising in winter when bathing is common to 30–40% on busy days. Reported foreign visitor numbers were around 14,000 in 2006, 18,000 in 2009 and 23,000 in 2010. The 2011 Tohoku earthquake caused a dramatic temporary drop in visitors, but numbers later recovered.

FAQ

Where is Jigokudani Monkey Park located?

The park is at the far end of the Jigokudani Onsen valley in Yamanouchi, Shimotakai District, Nagano Prefecture, in the Yokoyu River valley that rises in Shiga Kogen.

When did the park open?

The company was established and the park opened on June 3, 1964.

How many macaques are in the troop and how many bathe?

At the end of 2012 the troop numbered about 160, and approximately 50–60 entered the hot spring between December and March.

Can visitors feed or touch the macaques?

No; visitor feeding is strictly prohibited, visitors must not touch the macaques and must follow rules such as keeping distance, not staring and not using selfie sticks.