Yellowstone National Park is the first national park in the world. Located in the states of Wyoming (96%), Montana (3%), and Idaho (1%), Yellowstone is 2,219,789 acres, larger than the states of Rhode Island and Deleware combined. While not nearly the largest state in the United States, it is one of the best known and most visited, receiving an estimated 3 million visitors per year (the record year was in 1992 when the park received 3,144,405 visitors). The park is well known for its numerous geothermal features including geysers, hot springs, mud pots and fumaroles.