A cornerstone of Japanese culture, onsen runs the gamut—but these destinations in Kyoto, Tokyo, and across the countryside are the height of luxury.

An onsen is a traditional Japanese hot spring, featuring baths that are fuelled by geothermal activity beneath the Earth's surface. These baths, which can be found all over Japan due to the country's ...

(CNN) — It was a cold February day in northern Japan, snow piled high outside the onsen locker room windows as I slipped out of my clothes. Nervously, I stepped into the plumes of steam wafting from ...