<P> One of the longest bridges when it was built, the Seven Mile Bridge connects Knight's Key (part of the city of Marathon in the Middle Keys) to Little Duck Key in the Lower Keys . The piling - supported concrete bridge is 35,862 ft (10,931 m) or 6.79 miles (10.93 km) long . The current bridge bypasses Pigeon Key, a small island that housed workers building Henry Flagler's Florida East Coast Railway in the 1900s, that the original Seven Mile Bridge crossed . A 2.2 - mile (3.5 km) section of the old bridge remains for access to the island, although it was closed to vehicular traffic on March 4, 2008 . The aging structure has been deemed unsafe by the Florida Department of Transportation . Costly repairs, estimated to be as much as $34 million, were expected to begin in July 2008 . Monroe County was unable to secure a $17 million loan through the state infrastructure bank, delaying work for at least a year . On June 14, 2008, the old bridge section leading to Pigeon Key was closed to fishing as well . While still open to pedestrians--walking, biking and jogging--if the bridge were closed altogether, only a ferry subsidized by FDOT and managed by the county would transport visitors to the island . </P> <P> After the destruction of the Keys railway by the Labor Day Hurricane of 1935, the railroad bridges, including the Seven Mile Bridge, were converted to automobile roadways . This roadway, U.S. Highway 1, became the Overseas Highway that runs from Key Largo south to Key West . Today this unique coastal highway allows those in automobiles to travel through the tropical islands of the Florida Keys and view exotic plants and animals found nowhere else on the US mainland . The Overseas Highway allows travelers access to the largest coral reef chain in the United States that runs through the Florida Keys . </P> <P> Following the Cuban Revolution, many Cubans fled to South Florida . Key West traditionally had strong links with its neighbor ninety miles south by water, and large numbers of Cubans settled there . The Keys still attract Cubans leaving their home country, and stories of "rafters" coming ashore are not uncommon . </P> <P> In 1982, the United States Border Patrol had established a roadblock and inspection points on US Highway 1, stopping all northbound traffic returning to the mainland at Florida City, to search vehicles for illegal drugs and illegal immigrants . The Key West City Council repeatedly complained about the roadblocks, which were a major inconvenience for people traveling from Key West, and hurt the Keys' important tourism industry . </P>

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