The first Overseas Highway, also known as State Road 4A, consisted of two roadway segments completed by 1928, one spanning from Key West to No Name Key and the other from Key Largo to Upper Matecumbe Key, with ferries transporting cars between them. The roads were constructed of local rock and marl. In the 1930s, World War I veterans were sent as part of the Federal Emergency Relief Administration to work on bridges to close the gap, but construction was cut short when the 1935 Labor Day hurricane claimed the lives of more than 400 workers and their families. The disaster sparked debate over whether to rebuild the Florida East Coast Railway or the highway, and Monroe County chose the highway, with the railway’s Bahia Honda Bridge converted for automotive use. In 1938, a toll road linked Lower Matecumbe to Big Pine Keys and created the first continuous road from Miami to Key West. During World War II, the Overseas Highway shifted from State Road 4A to a new alignment using the Florida East Coast Railway’s straighter route, and most of State Road 4A was abandoned or became local streets, while the section north of this point is part of the Florida Keys Overseas Heritage Trail.