Ferries serve two audiences within national parks: those visitors who want to experience a water-based tour (such as Fort Sumpter, or the Statue of Liberty) and those who need transportation across a river (e.g. Mammoth Cave National Park).
Boston Harbor Islands
The 200-passenger Harbor Islands Express ferries to Georges and Spectacle Islands leave regularly from several mainland piers; the primary pier is at Long Wharf North in Boston. Smaller ferries serve Lovells, Grape, Bumpkin, Peddocks, and Thompson Islands. Schedules vary in the spring, summer, and fall. The two most popular tours are:
- Georges Island: Tour the National Historic Landmark, Fort Warren, a 19th-century granite stronghold built to defend Boston. There are free ranger-guided tours.
- Spectacle Island: Take a swim from a lifeguard-supervised beach. Hike along five miles of trails with spectacular views of the Boston skyline and harbor. A "green" visitors center has exhibits.
The park also offers day-long trips to four rustic islands: Grape, Bumpkin, Peddocks, and Lovells Islands. Three of these islands offer camping.
Mammoth Caves: Green River and Houchins Ferry
The Green River bisects Mammoth Cave National Park, and can be crossed within the park via Green River Ferry or Houchins Ferry. These two ferries represent two of the few remaining rural ferries now operating in America.
The Green River Ferry operates year-round; the Houchins Ferry operates from March to November.
These are small vehicle-transport ferries. Vehicles cannot exceed 8 tons, and must be no more than 16 feet in length.
Neither ferry operates during hazardous river conditions.