Japan's great onsen town — steaming streets and seriously strong water.

Kusatsu is Japan's most celebrated hot-spring town, built around the Yubatake — a steaming field of wooden channels cooling scalding spring water right in the town center. At three to four hours from Tokyo it's a stretch as a day trip, so stay the night: dawn baths, the yumomi water-stirring show, and strongly acidic water that feels like the real thing.