Where is Yellowstone national park located inside of?

Yellowstone actually lies in 3 states. WY has the largest part, ID is to the western part of Yellowstone and MT is to the north. Take a look at visitingparks.com/YellowstoneMap.htm for a map. Click on the Ter option for the best view and then zoom out (-) For videos and park maps, go to visitingparks.com/Yellowstone.htm If you plan on going to the park, it is just magnificent.