ABSTRACT
In their simplest form, most roads are ridges, shoulders and sidewalks are plane surfaces, and curbs are mini walls. Roads are built as ridges in order to ensure fast surface drainage and to prevent ponding. Roads vary depending on whether they are located in rural or urban areas. Roads have three distinct parts: a longitudinal slope called a gradient, which determines whether a road is ascending or descending in relation to the surrounding topography; the centerline which is often a ridgeline called the crown of the road, and the cross slope which makes the road slope away from the crown on both sides or creates a uniform cross slope across the road. In addition to sidewalks, there are multiuse paths and walkways that are not tied to road structures. In addition, guidelines set by the Americans with Disabilities Act of 1990 provide standards for minimum and maximum slopes for accessible paths.
