The older bridge, originally known as the Knights Key-Pigeon Key-Moser Channel-Pacet Channel Bridge, was constructed from 1909 to 1912 under the direction of Henry Flagler and Clarence S. Coe as part of the Florida East Coast Railway's Key West Extension, also known as the Overseas Railroad.

After the railroad was damaged by the Labor Day Hurricane of 1935, the line was sold to the United States government, which refurbished Seven Mile Bridge for automobile use.

[4] The new bridge is a box-girder structure built from precast, prestressed concrete sections, comprising 440 spans.

The event began in 1982 to commemorate the completion of a federally funded bridge building program that replaced spans that oil tycoon Henry Flagler constructed in the early 1900s to serve as a foundation for his Overseas Railroad.

[6] The bridge has been featured in films and television series, such as Road House, Licence to Kill,[7] True Lies,[8][9] 2 Fast 2 Furious,[10] Burn Notice, and is seen in the upcoming video game Grand Theft Auto VI.