The Seven Mile Bridge is a bridge in the Florida Keys, in Monroe County, Florida, United States. It connects Knight's Key (part of the city of Marathon, Florida) in the Middle Keys to Little Duck Key in the Lower Keys. Among the longest bridges in existence when it was built, it is part of the Overseas Highway in the Keys, which is part of the 2,369-mile (3,813 km) U.S. Route 1.
There are two bridges in this location. The modern bridge is open to vehicular traffic; the older one only to pedestrians and cyclists. 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.
The total length of the new bridge is actually 35,862 ft (10,931 m) or 6.79 miles (10.93 km), and is shorter than the original. The bridge carries the Florida Keys aqueduct, supplying water to points west, as well as fiber optic cables, providing telecommunications to and from the lower Keys.
The bridge has been featured in films and television series, such as Licence to Kill, True Lies, 2 Fast 2 Furious, and Burn Notice.