As visitors drive along a scenic byway, they are focused on the surrounding scenery. They are probably not aware of the number of driving lanes, width of the driving lanes, shoulder width, construction materials, sharpness of the curves, how rock crops are treated, and how the road follows the topography. Yet these factors have dramatic effect on their experience.
While road design is influenced by the physical aspects of the terrain, road use, design speed, and the technical standards set by the local, State, or Federal governments, there is flexibility in roadway design.