I love the idea of hot springs. I have always chosen a bath over a shower when I have the time, and I usually try to make the time for a bath, so the idea of hot water available naturally appeals to me. One of the coolest spots I know of nearish to me is called Hot Springs Cove. There, water naturally bubbles up from the rock and flows to the ocean nearby. A series of pools and even a hot water waterfall are available. I have yet to visit, but I imagine a trip might be in my future.
Here two characters of mine, Erik the fisher cat and Agate the Lynx explore the wonders of nature. Alas they forgot to bring bathing suits, so underwear has to do. For those lamenting those pieces of cloth, I regret I can not control your imaginations and must remind you just what water does to white fabric.