Most bridges are built with the understanding that certain vehicles—trucks, trailers, tractors, etc.—are larger than ordinary cars and thus require more headroom.
Not this one. Whoever designed this bridge seems to have been under the impression that all vehicles are under 11 feet, 8 inches in height.
The result: Trucks that were over 11 feet, 8 inches before going under the bridge are now exactly 11 feet, 8 inches.
