Florida's Dry Tortugas National Park consists of seven small islands and covers nearly 65,000 acres, making it one of the smallest national parks in the National Park System. Fewer than 100 acres of this total space is dry land; most of the protected area consists of ocean.
Park visitors are allowed to swim in these waters. Snorkelers can get a glimpse of the protected ocean life that thrives in the park. There are also points of interest on land, with the largest island in Dry Tortugas hosting the site of a historic military fortress called Fort Jefferson, which dates back to the 19th century.