Island Hideaway at Florida's Fort Jefferson

While famous Key West hosts endless crowds of revelers, 68 miles west lies a little-known jewel in Florida's crown: Dry Tortugas National Park. Here it is possible to find the simplicity and beauty typical of the Florida Keys before the Overseas Highway brought the masses to the southernmost tip of the United States.

The group of islands, Las Tortugas, was named in 1513 by Ponce de Lon after the sea turtles that still nest on its beaches; they were later designated as "dry" because no fresh ground water exists here. The third of south Florida's national parks differs significantly from Everglades and Biscayne, both established to protect ecosystems and animals.

While Dry Tortugas was upgraded from a national monument in 1992 to protect 100 square miles of spectacular coral reefs and bird rookeries, it is the obsolete brick giant called Fort Jefferson that dominates both the seven-island archipelago and the imagination.

As Ranger Peggy Scherbaum says on her tour of the fort, "Tourists may think this is a government boondoggle when they first come in, but when they leave they feel about it the way the English feel about their castles."

Fort Jefferson was begun in 1846 to protect anchorages on the only shipping channel into the Gulf of Mexico. Building continued until 1875 with slaves of African extraction doing much of the construction under the direction of the US Army Corps of Engineers. As many as 40 million bricks were used for the inconceivably ambitious project.

Never completed, the fort nevertheless housed 2,500 soldiers, workers, and prisoners at a time during the Civil War. Dr. Samuel Mudd was the most famous prisoner, convicted of conspiracy for setting the leg of Abraham Lincoln's assassin, John Wilkes Booth.

The site remained strategic in the Spanish-American War of 1898: The USS Maine sailed to its demise in Havana Harbor from the fort's coaling docks. As recently as 1961, soldiers occupied the fort. Tales circulate that pockmarks on the magazine wall were caused by target practice before America's failed Bay of Pigs invasion of Cuba.

Three years ago, before ferries like the Yankee Freedom began taking visitors on the 3-1/4-hour trip from Key West, only sea planes, private charters, and private vessels had access to the park. Most people go out just for the day, but those who can do without the trappings of modern life may camp as I did under an idyllic ocean-front canopy of buttonwood and palm trees.

As of old, cisterns and saltwater distillation provide Fort Jefferson's Park Service residents with fresh water, with none extra for visitors. There are no bait and tackle stores, ice machines, or sundries available. All food, fresh water, and other necessities must be brought in, and all trash taken out.

Nineteenth-century troops ate bird eggs and fish, turtle soup, and occasionally, beef and pork from the livestock kept across the narrow channel at Bush Key. Now only the cries of thousands of sooty terns drift over from that little spit of sand. Pelicans with their great wings outstretched line the beach like sunbathers. Overhead, frigate birds with their seven-foot wingspans soar with balletic grace.

Across the moat and through the sally port, the fort's parade ground presents the most tranquil scene imaginable. Solitary benches under enticing shade trees look out on the vast green, flanked by the remains of once-splendid barracks that were damaged by fire and later demolished.

Fishing and shell-collecting were pastimes then as now, but the modern pleasure of snorkeling over multihued sea gardens of live corals was unknown to the conscripts. In the moat, which used to be filled with raw sewage and trash, are slow-moving starfish.

Christmas tree worms stud the brain corals on the moat's outside wall like feathery gems, vanishing into themselves at the slightest disturbance of the water. Purple sea fans undulate; a blue-and-yellow queen angel fish rides the waves pulsing in and out of a culvert. I was lulled by the constant wind and sun into the placid state of mind typically induced by an island vacation.

But I soon recognized the pitched battle of the elements raging in the now-peaceful fort. A frequent gale eats away the bricks; rainstorms wash out the mortar; condensation dripping through the ceiling forms stalactites and stalagmites, strangely organic among the regimented arches. Steel shutters that used to slam shut after the cannons were fired are rusting, causing the faade to crack off. This year, for the first time, an arch collapsed.

Nevertheless, at sunrise and sunset, I couldn't resist the urge to climb the spiral stairs for the twice-daily natural light show and take in the views from the top of the fort. Even the prisoners got to enjoy what one of them called "nature's panorama." The moat wall, which measures one-sixth of a mile around, affords views of distant Loggerhead Key's lighthouse by day and by night, under a brilliant star field.