Best known for its stunning display of vivid color, Yellowstone National Park is an undoubted national treasure. The reds, yellows and browns of the mud in the images below are derived from oxidation states of the iron in the mud.
Yellowstone – Colorful Mud Formations
Photos by Ravi 
Yellowstone is such an interesting visual experience. the painted pots, the geysers, the mountains—its such a fabulous place
Indeed Sylvia!