The Snow Monkeys of Jigokudani
The Japanese macaques of Jigokudani Yaen-Koen in Nagano Prefecture are among the most photographed wild animals in the world. A troop of over 160 macaques descends from the cedar forest to bathe in the natural hot spring pool beside the park’s entrance, and the sight of monkeys sitting in the steaming water with snow-covered branches overhead has become one of Japan’s most iconic winter images. The monkeys learned to use the hot spring in the 1960s and have passed the behaviour to each successive generation.
About Jigokudani
Jigokudani — “Hell Valley” — takes its name from the steam vents and boiling springs that emerge from cliff faces along the Yokoyu River valley. The park was established in 1964 specifically to study and protect the macaque troop, and the custom-built bathing pool (fed by natural hot spring water at approximately 43°C) was created to give the monkeys a reliable warm-water source through the severe Nagano winters, where temperatures drop to -10°C and snow accumulates to several metres.
The macaques are entirely wild — not fed by staff, not trained — but completely habituated to human presence after six decades. Visitors walk among the troop on the same paths, and the monkeys ignore human observers almost entirely unless someone makes sudden movements or gets too close to mothers with infants.
What to Expect
The hot spring pool is a constant feature regardless of season, but the classic snow-monkey photograph — animals in the pool with snowflakes falling — requires winter visits (December–March). In summer, the monkeys use the pool less frequently; they are still present in the valley but range more widely into the forest. Autumn foliage provides a different visual context but summer and autumn visits have far fewer visitors and more opportunities for close-up observation of non-bathing behaviour — foraging, grooming, infant play.
The park is open year-round, 365 days. Entry costs ¥800 for adults. No feeding the monkeys; no touching; no getting between a mother and infant. Photography is unrestricted. The walking path from the trailhead to the monkey pool is approximately 1.6km through forest — allow 30–40 minutes each way on packed snow paths in winter.
Getting There
The most practical base is Shibu Onsen or Yudanaka in Yamanouchi, Nagano Prefecture, accessible by Nagano Electric Railway from Nagano Station (40 minutes) and then local bus or taxi to the Jigokudani trailhead. From Nagano Station the full journey takes approximately 90 minutes. Shibu Onsen is itself a charming traditional onsen town with seven public baths for ryokan guests to use freely — combining a snow monkey visit with a night at Shibu is one of Nagano’s most complete travel experiences.
Day trips from Tokyo are possible via Hokuriku Shinkansen to Nagano (90 minutes), but the round trip leaves limited time at the park; an overnight stay is recommended.
Behaviour to Watch For
Beyond the bathing, Jigokudani offers extended observation of complex primate social behaviour. The troop has a clear dominance hierarchy; access to the best bathing spots reflects rank. Grooming pairs maintain social bonds; juvenile males chase each other through trees; mothers carry infants on their backs or let them explore at arm’s length. In late spring, newborns with distinctive pink faces and sparse grey fur cling to their mothers and begin tentatively entering the warm water for the first time — one of the most watched seasonal events in Japanese wildlife tourism.