3) Grand Prismatic Spring, Yellowstone National Park, Wyoming
There are several must-see attractions in Yellowstone National Park, but perhaps the most beautiful one is the Grand Prismatic Spring. The largest hot spring in the United States, this one features a dark blue center with nearly every color of the rainbow circling its edges. Its official dimensions are listed at 250 by 300 feet, with a depth of over 160 feet. You’ll find it a short (and easy) walk from most of the other main attractions of the park. The crazy natural colors in the spring come from pigmented thermophilic bacteria, which sounds strange, but almost guaranteed to become your favorite sight in the entire park.
