Yellowstone National Park's nearly 3,500 square miles seep slightly across state borders into Montana and Idaho, but its major attractions are contained in the northwest corner of Wyoming.

A car is necessary for visiting different regions and attractions ... so you'll want to use an official Yellowstone map (available online or at the park's five visitor centers) or specific ...

Yellowstone’s popularity overshadowed a relatively unknown Oklahoma national park. With so much competition, the park no longer exists.