Know what an onsen is? This Japanese word refers to the resorts and bathing facilities attached to the country's multitude of hot springs. Therapeutic hot spring baths are a long-standing Japanese tradition, and they're famous abroad partly because they've historically been nude and communal. Now, of course, many onsens allow patrons to wear bathing suits, although bathers are still expected to wash themselves thoroughly before entering the water. Mountain-dwelling snow monkeys are also known to enjoy a good dip, so if you do make it to a Japanese hot spring, don't be surprised if you make a furry new friend.

Photo by Flickr user mavesen