Jigokudani Yaen-koen

The park lies at 850 metres in the gorge of the Yokoyu River below Shiga Kogen, where steam rises constantly from vents in the cliffs. Winter brings more than a metre of snow and nights below minus 10°C. Jigokudani Yaen-koen opened in 1964. Staff put out food so the troop stays where people can watch it, and no fence or cage stands between you and the animals.

The bathing started by chance. Once feeding kept the troop around the valley, a young monkey learned to climb into the rotenburo at Korakukan, the inn next door, and others copied it. The park built a separate pool for the monkeys, and each generation has picked up the habit since. They use it to get through the winter cold and rarely bother with it in the warm months.

Keep food out of sight and hand any snacks in at the ticket window before you enter. Give the monkeys room: a long stare from close by reads as a threat to them, and a curious youngster that wanders up is your cue to step away. Selfie sticks and drones are banned, as is holding a camera over the bathing pool. Staff can send anyone out who ignores the rules.

Parking is short, so the park asks visitors to come by public transport. The Nagano Electric Railway reaches Yudanaka in 38 minutes on the limited express from Nagano, and a 15-minute bus runs on to the Snow Monkey Park stop. The express bus from Nagano Station toward Shiga Kogen also stops there, in about 41 minutes. In winter wear snow boots and carry light crampons for the walk in.