What is used in Vehicle Game to make roads?

I came across land scape like sprites all over the Vehicle game map which is used to used to make roads and fences.

I couldn’t select them so i couldn’t find out what are those. I want to know what are those how do i use them? Any documentations on them?

Those are landscape splines. You can find the spline tool in the Manage section of the Landscape editor. In short, you place splines where you want your roads and assign meshes to the spline sections. The meshes will deform to fit the spline, and you can also have the landscape deformed to match the splines. It’s awesome.