A watery wonderland where 99 percent of the park is submerged

Countries & Cities · Published 12 October 2026 Swipe more like this →

In short: Most national parks are defined by their sprawling landscapes and hiking trails. Dry Tortugas is different. Located 70 miles west of Key West, this remote archipelago is almost entirely underwater. To truly experience its beauty, you have to leave the land behind and dive into its coral mosaics.

Dry Tortugas National Park is one of the most isolated reaches of the Florida Keys, consisting of a cluster of seven small islands. While it offers secluded camping and rare birdwatching, the park's true scale is hidden beneath the surface; over 99 percent of its area is submerged in the Gulf of Mexico. This watery expanse includes some of the least disturbed coral reefs in the region, teeming with tropical fish like yellowtail snappers, parrotfish, and queen angelfish.

The park's centerpiece is Fort Jefferson on Garden Key, a massive 19th-century coastal fortress built to protect a strategic deep-water anchorage. Constructed from over 16 million bricks, it stands as the largest brick masonry structure in the Western Hemisphere. The fort carries a complex history, most notably housing Dr. Samuel Mudd, the physician who treated John Wilkes Booth after the assassination of Abraham Lincoln. Though initially viewed as a traitor, Mudd gained respect by treating soldiers during a deadly yellow fever outbreak in 1867.

Beyond the masonry, the park serves as a critical sanctuary for biodiversity. Bush Key serves as the sole primary site for breeding both brown noddies and sooty terns within the country, whereas majestic frigatebirds soar across the keys throughout every season. Nearly 300 shipwrecks—among which is the HMS Tyger, an 18th-century British warship—populate this diverse seabed, offering essential springtime and summer nesting habitats for endangered sea turtles.

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