This is a complete model railroad simulation program that allows you to design scenes by dragging and dropping objects on the ground, including tracks, locomotive engines, wagons, trees, animals, roads, buildings, etc.
You can design the set any way you'd like. You can lay track on different levels and have them cross using switches.
The best thing about googol-Choo-Choo3D is definitely the fact that you can see the scene from multiple angles: from inside of a wagon, from inside the locomotive, from the point-of-view of the driver, etc.
In addition, you can use the model trains and other objects that you make with other CAD and 3D design programs.