Rainwater percolates through porous tufa rock until, deep in the earth, it meets hot molten rock. Here it is heated and begins to rise back to the surface until it bubbles out of numerous hot springs in the side of the hill in Hot Springs, Arkansas. When it comes out, it is a very hot 143F. Hundreds of years ago, native Americans came to the springs for soothing baths. In the early 1900s, wealthy people saw this as a place to cure their ills and soothe their pains. Large bathhouses were built at the base of the mountain and the hot water was pooled and the temperatures regulated for the different types of baths.