The relaxing sensation of soaking in an onsen—or Japanese hot spring—is so popular that even the country's monkeys take part in the tradition. At Jigokudani (Hell's Valley) Park just outside Nagano, snow monkeys soak in the hot springs on winter days and return to the forest at night.
The simian spa has been operating since at least 1963, when the snow monkeys were first observed bathing in the spring. They do so to ward off the cold—Jigokudani's harsh, high-altitude landscape is covered in snow for four months out of every year and winter temperatures drop to 14 degrees Fahrenheit.
Tourists are welcome to walk the mile-long path through the forest to see the snow monkeys in their spa. The Jigokudani website, however, warns that "bathing with monkeys is strictly prohibited in terms of health and hygiene as well as mental health."
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