You’re never far from water in the Florida Keys. Swimming, fishing, snorkeling, or just relaxing — the water is there to be enjoyed, no matter what your age or inclination.

Fort Jefferson, lying on a tiny island in the Dry Tortugas nearly 70 miles west of Key West, is a favorite spot for visitors. (Photo by Rob O'Neal, Florida Keys News Bureau)

One of the most enjoyable water experiences is a voyage aboard the 100-foot catamaran Yankee Freedom II to Dry Tortugas National Park and Fort Jefferson. Located 68 miles west of Key West in the Gulf of Mexico, Dry Tortugas is America’s most remote national park — and the six-sided Civil War-era fort just might be the largest brick structure in the Western Hemisphere.

Aboard the Yankee Freedom, you’ll find an air-conditioned main cabin equipped with comfortable benches and tables (if you’re like me, that’s where you’ll want to spend most of your time). The main deck also has three restrooms, including one that’s handicapped-accessible.

If you prefer being outside and don’t mind climbing stairs, you’ll love the second deck. Partly covered and partly open, it’s a great place for basking in the sun and spotting fish, sea turtles and other marine life.

The Yankee Freedom offers comfortable, entertaining daily voyages to the Dry Tortugas. (Photo courtesy of Yankee Freedom and Historic Tours of America)

Once the catamaran leaves its dock at Key West’s Historic Seaport, you can enjoy a bountiful breakfast on board. Shortly you’ll cruise past Boca Grande National Bird Sanctuary, Marquesas Key atoll, and the site of the shipwrecked Spanish treasure galleon Nuestra Señora de Atocha. An onboard tour guide provides commentary along the way, sharing his knowledge of the area.

The Dry Tortugas are actually seven tiny coral-and-sand islets that were discovered in 1513 by Ponce de Leon. He named them “Las Tortugas” for the numerous turtles he discovered there — and when no fresh water could be found, the word “Dry” was added to their name.

Massive Fort Jefferson stands on Garden Key, the Tortugas’ largest island, taking up almost the entire land mass.

The fort dates back to 1846, and chances are you’ll find its history as intriguing as I did. Key West was a Union stronghold during the Civil War, so Fort Jefferson was used to house the Union Army’s prisoners — including Dr. Samuel Mudd, who set John Wilkes Booth’s broken leg after Booth shot President Abraham Lincoln.

America's largest masonry structure, the fort welcomes people eager to explore the Tortugas' natural and historic wonders. (Photo by Rob O'Neal, Florida Keys News Bureau)

Several years after his imprisonment, when the fort’s only doctor died in a yellow fever epidemic, Dr. Mudd treated other prisoners and soldiers who contracted the disease. Eventually, in part because of requests from his captors, President Andrew Johnson granted Dr. Mudd a full pardon.

Today, Yankee Freedom passengers can take a guided tour of the fort and view Dr. Mudd’s cell (bleak enough to make me shiver), or stroll the grounds on their own.

If you’re a birder, be sure to bring your binoculars. Hundreds of species can be found on nearby Bird Key, and you can walk outside the fort and search for them.

Snorkelers and swimmers, bring your bathing suits. Snorkel gear is provided, so you can slip into the crystal blue water for a pleasant hour of activity (you’ll find a shower on the Yankee Freedom that’s great for washing off saltwater).

Tortugas visitors can view seemingly endless vistas of sea and sky. (Photo courtesy of Yankee Freedom and Historic Tours of America)

And if you’re feeling lazy, simply relax on Garden Key’s sandy beach or under the trees.

Later, you’ll return to the boat for a buffet lunch of cold cuts, salads, sandwiches, and desserts set up by the crew — followed by more time to explore the fort and Garden Key. On one of my trips I was escorting a CNN reporter, and we climbed all over the fort shooting photos and checking out the panoramas of turquoise water and sky.

Passengers tend to be quiet on the journey back to Key West, lulled by the wash of waves, savoring a snack or drink as they recall the highlights of their day.

Whether you’re interested in history, architecture, birding, or just having a good time, you can’t beat a day trip to Dry Tortugas National Park. But don’t take my word for it … come down and experience it for yourself.