Yellowstone National Park lies on top of a huge super volcano. That is what creates the boiling geysers, which there are approximately 500 of. The highest temperature recorded in a geyser was 459 degrees fahrenheit. The park also has many colorful springs such as Grand Prismatic, Lion Geyser, or Crested Pool.
You can see many species of wild life too. During my visit I saw two Grizzly Bears, two Moose, and many Elk and Bison.
Yellowstone national park is a unique place, and I would go back any day.