The pass is valid for 7 days. Boats and ferries that will bring you to Fort Jefferson include Seaplanes of Keywest, Sunny Days Catamarans, and Yankee Freedom. They collect the park's admission fee from their passengers in addition to their fare. National Parks Pass, Golden Eagle, Golden Age, and Golden Access Passports honored.
If you are looking for an adventure in the Florida Keys that is off the beaten path, you should consider visiting the remote Dry Tortugas National Park. The Dry Tortugas are seven islands created from the coral reefs and sand located off the coast of Key West. The park is located 70 miles off of the coast of Key West and you can arrange to visit by boat or seaplane. We took the 2 hour boat ride and spent the day at the park exploring the remnants of Fort Jefferson, snorkeling in the pristine waters, enjoying the beach and eating lunch provided by our outfitter. It is a beautiful place to spend a day. You need to make reservations in advance and also make sure to pack all the you will need for the day as there are no amenities on the islands.
Now, to really get away from it all, plan a trip from Key West to Dry Tortugas, where you can snorkel and explore Fort Jefferson, which once served as a prison that held Dr.Mudd, the physician who patched up Lincoln assassin John Wilkes Booth. Restrooms are the only facilities.