#1. The 7 Mile Bridge
The original Seven Mile Bridge was part of a railroad, the first solid transportation route built from southern Florida to the Keys by Henry Flagler in 1912. To connect Florida to other industrial networks, he envisioned a grand railroad, eventually known as the Florida East Coast Railway. In 1935, that railroad was taken over by the US government and turned into a roadway.
The most impressive stretch of this railway was known as the Seven Mile Bridge, one of the longest segmented bridges in the world. In 1935, however, it was badly damaged in a hurricane and sold to the United States government. The government rebuilt and widened it for automobile use, and added a section that could open to allow for passing ships. This new road was also heralded as a marvel of modern engineering, built over the constant challenge presented by construction in even the calmest of waters.