This 440-acre island is the home of the last government-manned lighthouse (built in 1858) in the United States. Now a wildlife refuge, Egmont Key was a camp for captured Seminole Indians during the Third Seminole war and was a Union Navy base during the Civil War.

Several boats offer snorkeling excursions to this island, visitors can snorkel over grass beds and ruins of two gun batteries from the fort. Or rent a boat and sail down to privately enjoy the unspoiled beach and explore the ruins of the ghost town of Fort Dade.