Jigokudani Monkey Park (地獄谷野猿公苑, Jigokudani Yaen Kōen, map) is located in Yamanouchi, Nagano Prefecture. Yamanouchi, located in the Japanese Alps (wiki), one of the largest ski resorts in Japan.
It is famous for its large population of wild Japanese macaques (Macaca fuscata), more commonly referred to as snow monkeys, that go to the valley during the winter, foraging elsewhere in the national park during the warmer months. The monkeys descend from the steep cliffs and forest to sit in the warm waters of the onsen (hotsprings).
However, since the monkeys are fed by park attendants, they are in the area of the hot springs all the year round, and a visit at any season will enable the visitor to observe hundreds of the macaques.
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The name Jigokudani, meaning “Hell’s Valley”, is due to the steam and boiling water that bubbles out of small crevices in the frozen ground, surrounded by steep cliffs and formidably cold and hostile forests. It is part of the Jōshin’etsu-kōgen National Park (wiki, map), and is located in the valley of the Yokoyu-River.
The Jōshin’etsu Kōgen National Park is a popular tourist destination for skiing, mountain climbing, hiking, and onsen hot spring resorts. The Eastern Area holds the popular skiing areas of Sugadaira (map) and Shiga Kōgen (map).
The Shiga-Kusatsu-Kogen Ridge Highway traverses this section of the park, connecting the Yamanouchi Hot Springs, including the onsens of Yudanaka, in the north with the resort town of Karuizawa (map), Nagano Prefecture in the south.
Karuizawa is a popular year round resort offering many outdoor sport, hot spring and recreational activities. Convenient road and rail access from central Tokyo, has ensured Karuizawa’s popularity as a location for second homes and resort hotels since the Meiji era.
The town is known for its historic shopping street known as “Ginza dōri” or “Kyū-dō” (Ginza Street, or the Old Road, map) and association with both Japanese royalty and visitors such as John Lennon and Yoko Ono.
For sorting through transport schedules and fares, HyperDia is an invaluable companion; it computes to-the-minute directions including connecting trains, as well as buses and planes.
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BUS > Buses are plentiful in Japan, and over the last few decades they have evolved into a major mode of intercity transportation, especially for overnight travel. Major operators of intercity include JapanBuslines.com • WILLER • JR Bus (kakuyasubus.jp) • kate.co.jp. >> (*Bus travel in Japan)
RAIL > Central Japan Railway Company • West Japan Railway Company • East Japan Railway Company. >> (*Rail travel in Japan)
AIRPORTS > Most international flights arrive at either Narita Airport near Tokyo or Kansai Airport near Osaka; a smaller number use Chubu International Airport near Nagoya.
Japan has many great opportunities for bikers. Bike rentals can be found throughout the country, especially near popular routes. Some routes (like the Shimanami Kaido Bikeway, which takes you from Onomichi on the main island to *Imabari in Shikoku) have been set up specifically for bikers.