You watch a short intro before you get to the main menu.
The main menu. You can start a new park, load a park, or learn the game through the tutorial.
Choose where in the US you want to start building. The location you choose determines what creatures and plants will survive in your park.
All parks start out small. Those trees are small now...
...but they will eventually grow much bigger.
This talking frog can get pretty annoying. Fortunately, he can be turned off in the options menu.
Just like in real life, if you don't maintain a balanced ecosystem, certain plants and animals will overpopulate your park.
Some idiot decided to dump his trash in the forest. My park now has a hefty population of rats and hypodermic needles.