Pleasant in winter when shrouded in snow but far less appealing when seasonally bare, Yudanaka is a sprawling hot-spring town, best known for this wildly popular, though rundown, zoo, made famous by the 1992 film Baraka, where wild monkeys appear to bathe in natural onsen pools. In operation since 1964 and showing its age, the park sees thousands flock here each year to see the over-photographed troupe of Japanese macaques who are lured into the pools with food.
They're at times a little savage as they run wildly around you on the paths to the man-made onsen. The monkeys are a few hundred steps climb from the car park, which is itself at the end of a 1.6km winding uphill road.
The ruse is most convincing in winter when snow hides the industrial debris by the river; although the only way in is via a limited operation shuttle bus on that slippery, windy road.
If you're determined to make the trip, take the Nagano Dentetsu line from Nagano to the Yudanaka terminus (tokkyū ¥1260, 45 minutes), then take the bus for Kanbayashi Onsen Guchi and get off at Kanbayashi Onsen (¥230, 15 minutes, eight daily). Walk uphill along the road about 400m until you see the sign reading 'Monkey Park', then begin your rather gruelling uphill walk.