What is horizontal curve?

A horizontal curve is a geometric feature used in road design, representing a section where a roadway changes direction horizontally. It is usually characterized by a smooth, arc-shaped path that allows vehicles to navigate turns safely. The radius of the curve is crucial for determining the speed at which vehicles can safely travel, influencing design elements such as superelevation and sight distance. Properly designed horizontal curves enhance safety and driver comfort by minimizing abrupt directional changes.