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Galleries: World's best skinny-dipping spots
TRADITIONAL ONSEN, JAPAN
Japan's tradition of hot-spring bathing - onsen - is enshrined in the nation's culture. Located on the Pacific Ring of Fire, Japan bubbles with volcanic activity and there are thousands of bathing houses serving locals and tourists alike. Japan's army of salary people view onsen as the perfect stress buster, a place to unwind and shake off the city's shackles. Naturally, you can only do that if you're butt naked. It's a philosophy some Westerners find hard to grasp, but if you're prudish most onsen offer single-sex bathing. If you get the chance, it's an experience not to be missed.
More: See www.secret-japan.com,
which has a database of over 100 onsen from around Japan, complete with entry fees and opening times.