Lake Pontchartrain Causeway Bridge.
The original 23.86 mile-long structure, which now carries the Southbound traffic, was designed by the firm of Palmer & Baker. When opened in 1956, the structure was the longest bridge in the world by more than 15 miles. In building the bridge, which took just fourteen months, assembly-line, mass-production methods were utilized for the first time in the construction of a bridge. It was designed to employ hundreds of identical, hollow concrete pilings, concrete caps, and pre-stressed deck sections manufactured at an on-shore facility and barged into place. Engineering News-Record acclaimed the project to be "a bold venture requiring unusual foresight, ingenuity and resourcefulness." Opened: August 30, 1956.
Causeway Toll Plaza, Mandeville, LA, United States