The breathtaking majesty of the American West is on full display at Yellowstone. There are gorgeous mountains, lakes, rivers, and waterfalls, and that's not all. Yellowstone is situated over a massive caldera, or supervolcano, which is what causes the park's geysers and other characteristic geothermal features. Families travel from far and wide to witness the reliable eruptions of Old Faithful, the park's most famous geyser. There is a Heritage and Research Center that explores the natural history of the area, but it is best experienced firsthand. Keep an eye out for wildlife including the American bison, pronghorn, and grizzly bears.