Shortly after the U.S. bought Florida from Spain in the early 1800s, contradicting Navy reports led to construction of Fort Jefferson in the isolated Dry Tortugas. The strategic location of the islands was meant to secure trade in the Gulf, and naval supremacy in the Americas.
The Dry Tortugas
A small group of 7 islands, 67 miles off the coast of Key West, Dry Tortugas consists of Loggerhead, Garden, Bush, Long, Hospital, Middle, and East Key. As the name implies, none of them harbor fresh water, though their isolated location is ideal for birdwatching with nearly 300 species of migratory birds, snorkeling, viewing sea turtles in early summer and fishing.