Non-passing sight distance along a road is the longest distance at which the driver of a moving vehicle, may see an obstacle on the pavement

Highway engineering (also known as roadway engineering and street engineering) is a professional engineering discipline branching from the civil engineering subdiscipline of transportation engineering that involves the planning, design, construction, operation, and maintenance of roads, highways, streets, bridges, and tunnels to ensure safe and effective transportation of people and goods. (Source: Wikipedia)