The Florida Keys' Longest Scenic Bridge Takes You Across Miles Of Stunning Emerald Waters

America loves its highways. Throughout the mid-20th century, road construction was in its heyday, as efforts were afoot across the country to build connecting spans of concrete and asphalt so Americans could get from one end of the country to the other. It was the age of the American road trip, and from Route 66 to the Pacific Coast Highway and its stunning beaches, these connecting ribbons of roads linked U.S. citizens together in a way that persists even today.

But perhaps no stretch of highway was more ambitious than Florida's Overseas Highway — a 113-mile stretch of largely elevated concrete situated over the area's verdant waters that includes the iconic Seven Mile Bridge. The state's longest bridge was recognized as an example of highway engineering genius when it was constructed, as it enabled the Overseas Highway to connect Key Largo to Key West. Without the bridge, the Overseas Highway doesn't tickle the tropics and deliver tourists and supplies from the mainland of the Florida peninsula to America's southernmost point in the Caribbean.

Today's Overseas Highway was initially constructed as a railroad route by entrepreneur and businessman Henry Morrison Flagler and completed when he stepped off the train in Key West in 1916. But when a hurricane all but destroyed the railroad in 1935, the route was sold to the U.S. government, which converted the route to an automotive highway that opened in 1938. Since then, the most celebrated section of the highway that connects the Keys to the mainland is the Seven Mile Bridge (though it actually only measures 6.7 miles).

Yes, the Overseas Highway is still the most popular and most affordable way to access the Florida Keys — but it's much more than just a means to get from Key Largo to Key West. The Overseas Highway and the celebrated Seven Mile Bridge are rich in Florida history. The original Seven Mile Bridge was the most challenging span of Flagler's railroad construction project; in order to achieve its completion, he actually required his team to invent new construction technology as it was building the span over open water.

Today, the Seven Mile Bridge is really two bridges: the original bridge that started as a railroad route and the safer and more modern bridge that was completed in 1982 and largely enabled tourist traffic to get all the way to Key West without suffering through any significant traffic snarls. Before the bridge was improved, it was a skinny, two-lane road that required white-knuckled attention from drivers as they navigated their vehicles over the open water. Today's version hardly registers at all on the "pucker scale," and without it, tourists would miss some great attractions, like John Pennekamp State Park and its world-famous snorkeling, or the Rain Barrel artisan village that attracts visitors all year long. 

While Flagler's railroad served as a connector between the Florida mainland and the Keys, the notion of a vehicle highway really got started in 1919, during the Florida land boom. With real estate becoming scarce, developers at the time wanted to access the thousands of acres of undeveloped land in the upper Keys by automobile. While a bridge crossing the emerald-hued water now seems like the logical answer to this quandary, it took a tragedy for the Overseas Highway — and today's version of the Seven Mile Bridge — to become a reality.

On Labor Day 1935, the largest (at the time) hurricane to ever hit Florida took aim at the Keys. The hurricane pushed a 17-foot storm surge into the Keys and all but destroyed the railroad in the area. Ultimately, more than 400 construction workers died in the storm. It's likely the reason that the U.S. government purchased the route and completed the highway and the famed bridge, both deemed necessary at the time by the demands of commerce.

Of course, today, the Seven Mile Bridge is largely a tourism delivery mechanism and the highlight of one of America's great road trips. This iconic passage over the stunning flats of southern Florida should be on every ambitious road-tripper's list. It's just under 100 miles from Key Largo to Key West, and, with light traffic, the trip takes about two hours. But, with so much to see along the route (including a "secret" state park), wise motorists should devote a day to the famous highway, making sure to take the time to marvel at the Seven Mile Bridge.