It took a total of 66 years from the time of the very first proposal for the Chesapeake Bay crossing to the completion of the second span of the bridge in 1973. Although first proposed in 1907, it wasn't until 1949 that construction of the first span commenced.
The first proposal for a bridge, in 1907, suggested a crossing between Miller Island and Tolchester Beach. There were several proposals after that, but it wasn't until 1938 that the location of Sandy Point to Kent Island was settled upon. World War II and problems with funding delayed construction of the bridge until 1949 and the original bridge was finished by 1952. However, traffic volumes doubled within the first decade of operation, creating the demand for expansion.
By 1964, a study concluded that a parallel span was needed, and this was completed in 1973. The bridge is 4.5 miles long and connects the eastern and western portions of Maryland.