Hot springs are natural features resulting when ground water is heated (sometimes far beyond the level of human endurance) by geothermal forces and brought to the surface, typically becoming diluted with cool surface water on the way. Many are in attractive locations and are scenic (e.g. the geysers of Yellowstone National Park, Kamchatka, New Zealand, etc.) or celebrated (e.g. the original town of Spa), hence are attractions or even destinations in their own right. However, for the hot-spring aficionado, the greatest pleasure comes not from just looking at the spring, but from getting into the water for its therapeutic powers, not to mention just because it feels good -- really good. This article will help travelers get the most out of their hot-spring experiences world-wide.