Today we went to see a lot of the thermal features in Yellowstone. We began at the Artist Paint Pots, bubbling mud pots which are basically hot springs that have dissolved the rock to make mud in different colors. Next was the Norris Geyser Basin, hiking around the Porcelain Basin (because the ground is white from the minerals) and Back Basin. The landscape looks prehistoric, with steam vents hissing, the sulpher smells, pools of water bubbling. You really feel as if you are in the crater of a volcano (which you are) with only 5 miles of the earth's crust between you and volcanic magma. We went out the north entrance to shop and back in to swim at the Boiling River, then to see the Mammoth Hot Springs area. One amazing thing to see after another.