US 1 (the Overseas Highway) is 113 miles long and runs from Key Largo to Key West. The Labor Day Hurricane of 1935 destroyed most of the islands and the original railroad bridges and the remnants of these bridges were never rebuilt but were later converted for auto traffic. If you have time, research that hurricane. You won't be disappointed.
The Florida Keys are a coral cay archipelago (Google it) and they begin about 15 miles south of Miami and extend westward to Key West, the westernmost of the inhabited islands, down to the uninhabited Dry Tortugas.
