Marathon then became business central. Cuban ships brought pineapples and limes to transport throughout the US. Thus the trade within the Caribbean increased as well. The sponge and cigar industry thrived with the help of the railway. The first train to Key West carried its own Henry M. Flagler in 1912. Upon his arrival, he was greeted with heroism and joy. The Keys and its residents thrived with the help of the railroad.
After the Great Depression hit, the population of the Florida Keys dropped from 20,000 to 12,000. The sponge industry moved north to Tarpon Springs and the cigar industry to Tampa. An extreme loss of resources caused production to slow and residents started to turn to government assistance. In 1928, the county funded the establishment of roadways parallel to the tracks because as the American dollar grew, it was cheaper to haul cargo by car than by train. On Labor Day in 1935 (09/02/1935), the Florida Keys were hit by a hurricane that halted the project and too 432 lives. The production of the railway was never reconstructed due to expenses. The old overseas railroad still stands in some parts of the keys as a great reminder of the beginning of the eighth wonder of the world.