Creating a parametric bridge with curve modifiers

Dimitar P. writes:
Creating a parametric bridge in blender can be highly intuitive and parametric. Time-capture of the process of creating a parametric, curve-dependent road with the following process:
- create a simple mesh for a road part, and array with modifier
- add a curve modifier for a curve in the vertical direction
- add a curve modifier for a curve in the horizontal direction
- add structure

Very usefull tricks, I keep this in my mind.