The National Historic Landmarks in Florida are representations of a broad sweep of history from Pre-Columbian times, through the Second Seminole War and Civil War, and the Space Age. There are 47 National Historic Landmarks (NHLs) in Florida, which are located in twenty-two of the state's sixty-seven counties. Sixteen of the NHLs in the state are significant examples of a particular architectural style, eleven have military significance, ten are archaeological sites, three were the homes of well-known American authors, and one is associated with the development of the U.S. Space Program.