Fountain Paint Pot Nature Trail in Yellowstone National Park's Lower Geyser Basin is an extremely popular spot with a very congested parking lot. The walk is worth taking as it shows off an amazing array of thermal features in a small area.
The namesake of this hike, the Fountain Paint Pot, is similar to the Artists Paint Pots: an acidic spring that dissolves the surrounding minerals into a multi-colored muddy goo that bubbles ominously. There is a large cluster of geysers along the path that erupt frequently, some almost continuously, so there is always a lot of action at the far end of this loop. There are two very beautiful hot springs along the path very close to the parking area—the Celestine Pool and the Silex Spring—and a cluster of dead lodgepole pines that make a stark picture on the white mineral-crusted ground.