The Seven Mile Bridge is an iconic bridge in the Florida Keys of United States, stretching out into the open sea, connecting Knight's Key in the Middle Keys to Little Duck Key in the Lower Keys. At the time of its completion in 1982, it was the longest continuous concrete segmental bridge in the world, and is currently one of the longest bridges in America.
Seven Mile Bridge actually consist of two bridges in the same location. The older bridge, originally known as the Knights Key-Pigeon Key-Moser Channel-Pacet Channel Bridge, was constructed from 1909-1912 as part of the Overseas Railroad. After the railroad sustained considerable damage during the Labor Day Hurricane of 1935, the bridge was refurbished for automobile use only.
Dismantled tracks was recycled, painted white, and used as guardrails. It had a swing span that opened to allow passage of boat traffic, near where the bridge crosses Pigeon Key - a small island that once served as the work camp for the Florida East Coast Railway. When Hurricane Donna in 1960 inflicted further damage, decision to construct a new bridge was made.
A new, wider and sturdier Seven Mile Bridge was built right next to it from 1978 to 1982. When that happened, the original Seven Mile Bridge was nudged out of Florida’s transportation system. The vast majority of the original bridge still exists, used as fishing piers and access to Pigeon Key, but the swing span over the Moser Channel of the Intracoastal Waterway has been removed.
The total length of the new bridge is just under seven miles at 6.79 miles (10.93 km), and is shorter than the original. Each April the bridge is closed for approximately 2.5 hours on a Saturday and a "fun run," known as the Seven Mile Bridge Run, of 1,500 runners is held commemorating the Florida Keys bridge rebuilding project. 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.
The old bridge is still a popular spot with both locals and tourists, but it’s slowly falling apart. Salt water and storms are eroding the bridge faster than the state can afford to repair it. Much of the bridge is now closed – only a 2.2 mile section of the Old Seven Bridge is still open to pedestrians and cyclists.
Two years ago, a nonprofit community group called “Friends of Old Seven” was formed to try to preserve, and if possible, repair the bridge. The Florida Department of Transportation, which owns the bridge, cannot afford to sink a lot of money into the bridge’s upkeep, but is still willing to donate half of the $18 to $20 million required to repair the bridge. The community is now working hard to put up the other half.