A bridge is a structure which is built over some physical obstacle such as a body of water, valley, or road, and its purpose is to provide crossing over that obstacle. It is built to be strong enough to safely support its own weight as well as the weight of anything that should pass over it.

Bridge Designations
• If it carries road traffic or railway traffic or a pipe line over a channel or a valley: Bridge
• If it carries the traffic or pipe over a communication system like roads or railways: Fly-over/Over-Bridge
• Bridge (several small spans) constructed over a busy locality, a valley, dry or wetland, or forming a flyover to carry the vehicular traffic: Viaduct