What type of device is typically mounted at the side of the roadway to indicate alignment?

Delineators are vertical devices placed at the edge of the roadway to provide guidance and indicate alignment for drivers. They typically come in the form of plastic or fiberglass posts that are reflective, allowing them to be visible in low-light conditions. Their primary function is to enhance roadway visibility by clearly marking curves, edges, and other alignment features, which helps drivers stay oriented and reduces the risk of accidents.

In contrast, other devices like flashing lamps are generally used to alert drivers at specific locations, such as intersections or pedestrian crossings, rather than to indicate road alignment. Bollards are used for traffic control and to prevent vehicles from entering certain areas, while traffic cones are often employed temporarily for work zones or to mark hazards. While these other devices serve important functions in road safety, they do not specifically fulfill the role of indicating roadway alignment as effectively as delineators do.