Fort Jefferson, Dry Tortugas
Why: The largest masonry fortification the United States has ever built is located on a pretty spit of land about 70 miles off the coast of Key West. The sea here is cerulean, the turtles are easy to spot, and the sands are as white as clouds. Dry Tortugas National Park is one of the most remote national parks, which also makes it one of the most vulnerable to the effects of global warming. Harsher and more frequent storms are expected to increase in the Gulf due to the warming air and water surface temperatures, leaving this important historic site in the path of certain destruction. "Fort Jefferson is the poster child for making the investment in trying to save all these places. If we don't make that decision to save it," says Adam Markham, Deputy Director of Climate and Energy at the Union of Concerned Scientists, "it's going to be severely damaged and lost eventually." When it was built in 1847, the "masonry at the base of the fort was not expected to be under the water. But every day, the water is getting higher and eating away at it," says Markham.
What to do: Bring camping equipment, snorkeling gear, supplies and an underwater camera on board the Key West-based high-speed Yankee Freedom catamaran for an overnight stay at one of eight campsites next to Fort Jefferson. After pitching your tent on the beach, dive into one of the world's largest barrier reefs, where shallow waters (5-15 feet) and rich marine life, like nurse sharks, large turtles, and butterflyfish, make the Dry Tortugas a snorkeler's paradise.
More info: drytortugas.com