South Beach

South Beach is the sandy swimming beach on Garden Key’s south side, just past the campground and outside Fort Jefferson’s moat wall. It is one of three designated Garden Key swim areas, with a gradual slope and easy entry. Come for a straightforward shore swim with a 19th-century fort in the background; the setting and nearby reef are the draw more than miles of sand.

Garden Key is reachable only by boat or seaplane; ferry and seaplane trips run from Key West. From the ferry landing, head left past the campground and follow the moat wall to the beach. Treat it as a bring-your-own stop: plan food and drinking water before boarding, and check with your boat or seaplane operator about what is provided for the trip.

The beach gives swimmers a shore entry into the park’s reef setting. Fish and coral are often reported near the moat wall and pilings, though visitors also report murky water, so underwater visibility varies. Look for marine life from the water and keep your feet off coral and seagrass.

There is no lifeguard, and strong currents are possible. Stay within your ability, do not swim alone, and watch children closely. Stay out of the moat, do not dive from the walls, and never touch or stand on coral or seagrass.

Fort Jefferson was built from 1846 to 1875 to protect a strategic deep-water harbor on a major shipping route, but it was never completed or fully armed. It later served as a Civil War prison and then as a coaling station. Its best-known prisoner was Dr. Samuel Mudd, who treated John Wilkes Booth’s broken leg. From the beach, the long brick wall makes the fort’s scale part of the swim.

From the waterline, include the curve of sand in the foreground and the southern brick wall behind it. That shows how close the fort sits to the water better than a frame filled only with open sea.