Page Updated: November 16, 2023

Fort Jefferson

The Magazine - Fort Jefferson

Built with more than 16 million bricks and sprawling over 16 acres, Fort Jefferson lies on Garden Key; the second largest island in the Dry Tortugas. Its walls are 8 feet thick and contain more than 2000 arches.

The structure is said to be “so large that it slowly began to submerge the island on which it was built.” Construction lasted nearly 30 years - the fort was never finished and remains incomplete.

We began exploring Fort Jefferson as part of a tour with The Yankee Freedom. After 20 minutes or so, we chose to break off from the group and wander on our own. Sections of the fort are closed to visitors, but the majority is explorable.

Built for defense with 520 guns, the fort never saw battle and was primarily used as a prison.