The current structure was built to replace the Long Key Viaduct, which still stands parallel to the bridge. The Long Key Viaduct was completed in 1907 by
Henry Flagler as part of his
Overseas Railroad, the Key West Extension of the
Florida East Coast Railway (though the railroad would not fully reach Key West until 1912). The viaduct was built with a series of 186 concrete
arches, a design used by most of the railroad bridges in the keys. The Florida East Coast Railway often used the Long Key Viaduct in promotional material for the Overseas Railroad. Rail service was discontinued after the
Labor Day Hurricane of 1935 struck the area, which irreparably destroyed the railroad in the upper keys. The viaduct itself though was not heavily damaged. The Florida East Coast Railway then sold the remaining right of way and infrastructure to the state, who then built the Overseas Highway along the route. To accommodate the highway, the tracks on the bridge were replaced by a new two-lane wide reinforced concrete surface for automobile traffic. The Long Key Viaduct was listed on the
National Register of Historic Places on August 13, 1979, along with the original
Seven Mile Bridge and the
Bahia Honda Rail Bridge. The viaduct was replaced by the current highway bridge shortly after in 1982. After discontinuation of automobile traffic, the viaduct was repurposed again as a bike path and fishing pier. For the most part, the deck of the viaduct was reduced to its original width from the railroad era. There are several fishing platform on both sides of the bridge. The viaduct is now part of the
Florida Keys Overseas Heritage Trail, a multi-use bicycle and pedestrian path that will eventually run the entire length of the Overseas Highway. ==See also==