Yellowstone National Park is a World Heritage Site. It is primarily located in Wyoming, but it is also in Montana and Idaho.
Honorable mention: Roaring Mountain
10. Roosevelt Arch
9. Tower Fall and the Petrified Tree
8. Lamar Valley
7. Mud Volcano and the Mud Pots, plus the Sulphur Caldron
6. Yellowstone Lake and the West Thumb Geyser Basin
5. Hayden Valley
4. Grand Canyon of the Yellowstone, with the Upper Falls, Lower Falls, Artist Point, and Inspiration Point, near Canyon Village
3. Mammoth Hot Springs and Fort Yellowstone
2. Grand Prismatic Spring, part of Midway Geyser Basin – this basin is considered part of the Lower Geyser Basin and also includes the Excelsior Geyser, Turquoise Pool, and the Firehole River
1. Old Faithful, part of the Upper Geyser Basin – also located here is the Old Faithful Lodge