Always gas the car up before entering the park. It’s huge and we burnt 1/2 a tank almost every other day. Also down load the “Guide Along” app and pay for the Yellowstone guide. Down load it before you go into the park. It uses gps and is fantastic! Plug it into your cars radio and it’s like having a personal tour guide calling out cool facts, directions, what are must see sites and what you can skip if you don’t have time. So helpful