Wow, what a beautiful drive! Listed on the National Register of Historic Places, this incredibly scenic drive was originally the Overseas Railroad, envisioned by Henry Morrison Flagler and completed in 1912.
Unfortunately, the railroad met a tragic and dramatic demise in 1935 with the great Labor Day Hurricane. I highly recommend reading the Wikipedia article on the storm for a brief summary, or if you have time for a more detailed account, I really liked the one found here by Willie Drye. You can also read the statements before congress about the event of Honorable James Hardin Peterson, Honorable J. Mark Wilcox, Julius F. Stone Jr., Conrad Van Hyning, Ray W. Sheldon, Ivan R. Tannehill, Willis Ray Gregg, Charles P. Albury, Dr. James T. Googe, Hubert G. McKenzie, Frederick Bruce Ghent, Edwin A. Pynchon, David W. Kennamer, George E. Ijams, General Frank T. Hines, M. E. Gilfond, Harry B. Wirin, Aubrey W. Williams, Joseph F. Fecteau, S. C. Cutler, Harold Langlois, Laura Van Ness, and Governor David Sholtz in the hearing proceedings here.
After the railroad was destroyed, the government bought the land & immediately began work converting it to a road for cars. This is a road filled with bridges and scenic vistas, the most impressive of these is “Seven mile bridge” connecting the city of Marathon to Little Duck Key. Cars currently drive on the second iteration of the bridge, the first being unsafe to drive any longer.
Every April, the bridge is closed for one Saturday morning for a bridge run to commemorate the completion of the newer bridge sections. The old bridge has had sections removed to allow for unrestricted sailboat passage, but it is still accessible to pedestrians and bicycle traffic from the Florida Keys Overseas Heritage Trailhead.