Yellowstone National Park is located in the western United States. It spans 3,472 square miles (8,987 square km). Ninety-six percent of the park is located in the state of Wyoming, another three percent is in Montana, and one percent is in Idaho.
Also See the National Park Service Cartography Department's Maps
Official Park Map (pdf, ai & jpeg formats)
Large files available in Acrobat, Illustrator, and jpeg formats.