The Howrah Bridge, is lit up every evening with the majestic lighting making it look more beautiful. A bridge is a structure used to overcome an obstacle, natural or artificial, which is preferred to the continuity of a line of communication. We will bridge the strict sense if the obstacle is represented by a water course, we will have the viaducts if the obstacle is a valley orographic discontinuity, we will have the overpass if the obstacle is another way of communication of the same type as the crossing.
A bridge of this type has to span two or more cantilevers horizontal beams placed at one end, built from each end of the obstacle to be overcome the continuing construction, overhangs are approaching to join in with the centerline a single span suspended. It is a principle similar to that of two people who are touching each other the finger tips with your arms stretched out. The bridge spans are supported by a system of main batteries and anchors that come down to the banks. A construction of this kind is not difficult because the spans cantilevered sustain itself. This type of bridge is characterized by large deductibles in width.