Dry Tortugas: A Massive Brick Fortress in the Middle of the Sea

Why It Stands Out

The defining feature of the islands is Fort Jefferson, a staggering architectural feat that utilized over 16 million bricks. Construction began in 1847 to secure the Gulf Coast against piracy, but the project spanned thirty years and was never truly finished.

Despite its incomplete state, the fort is one of the largest masonry structures in the world, featuring a 70-foot-wide moat and walls designed to house hundreds of heavy guns. Beyond the brickwork, the surrounding waters earned a reputation as a "ship trap" due to treacherous weather and seasonal shallows.

The seafloor here is a maritime graveyard, preserving 17th-century vessel remains, antique glassware, and rusted cannons. The fort also served a darker purpose as a Civil War-era prison.

Its most notable resident was Dr. Samuel Mudd, the physician who treated John Wilkes Booth after the assassination of Abraham Lincoln.

Mudd was eventually pardoned after he heroically stepped in to treat a yellow fever outbreak that killed the fort's primary doctor.

Before You Go

Reaching this remote destination requires a seaplane or a ferry from Key West. While the boat ride is scenic, the seaplane offers a unique vantage point to spot sea turtles and sharks in the clear water below.

The environment is rugged; the sand can become extremely hot, and the historic masonry of the fort includes uneven stone surfaces, so sturdy closed-toe footwear is essential. Visitors are generally free to explore most of the grounds, provided they steer clear of active preservation zones.