From the Library website: The John F. Kennedy Presidential Library and Museum is dedicated to the memory of our nation's thirty-fifth president and to all those who through the art of politics seek a new and better world. Located on a ten-acre park in South Boston, overlooking the sea that he loved and the city that launched him to greatness, the Library stands as a vibrant tribute to the life and times of John F. Kennedy. Come tour our Museum which portrays the life, leadership, and legacy of President Kennedy, conveys his enthusiasm for politics and public service, and illustrates the nature of the office of the President. Students and scholars can also arrange to conduct research using our collection of historical materials chronicling mid-20th century politics and the life and administration of John F. Kennedy. The Kennedy Library is one of 12 Presidential Libraries administered by the National Archives and Records Administration. The Wikipedia page: JFK Library on Wikipedia

The morbidly curious might get more joy from visiting Castle Island, in South Boston, where Boston’s own Whitey Bulger (who was likely responsible for more than five deaths) did much of his plotting. Lore has it that the gangland leader chose to visit Castle Island because the wind made it difficult for the feds to tape his chats, but this could as easily have been achieved by the roar of traffic in front of the Old State House. A more likely reason for Whitey favoring Castle Island, besides the convenience to his house, is that it isn’t crawling with camera-toting tourists. This 22-acre urban park, connected to the mainland by pedestrian and vehicular causeways, is on both the State and National Register of Historic Places. Its centerpiece is Fort Independence, which played a vital role in the protection of the harbor during the turbulent days of early America. A stroll around the "Sugar Bowl"--a circular walkway that extends out over the water--makes for a fabulous afternoon, especially when topped off with a snack from Sullivan's, which is located at the foot of Fort Independence. Kids will love the renovated jungle gym, including a nod to the past with nostalgic 60's climb-on alphabet animals. The tot lot also includes swings for babies, big kids and handicap swings. Adults will enjoy the spectacular view of downtown Boston and water everywhere, dogs will appreciate they are welcome (leashed). There is even a dog drinking fountain. Everyone will appreciate that the harbor water is now clean enough to dip your toes in without fear.
The restrooms are currently being renovated but there are portable toilets available.

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Located at Castle Island and is the oldest continually fortified granite site on British North America, having played a variety of roles in colonial and revolutionary times. Fort Independence is a pentagonal five-bastioned fort built between 1834 and 1851, is the dominating feature of Island. Free seasonal tours of the Fort run every Saturday & Sunday from 12:00 noon to 3:30pm,from Memorial Day to Columbus Day. Tours last approximately 30 minutes. Strollers can not be accomodated on the tour.

Rolling Bridge Park is a small park which contains benches, interpretive signs and a big, red painted arm of the Old Colony Railroad Bridge that formerly occupied this site. Depending on where you sit, you can have either a view of the Gillette World Shaving Headquarters, the Vent Building,the freeway and commuter rail, or where the MBTA houses Redline trains when not in use. Interestingly, there really is no way to compensate for the immense buildings, cables, steel and concrete which engulf the area. These industrial surroundings make everything within the park seem odd and unrealistic. The trees do not function as park trees. Rather, they function as street trees meticulously organized and set in pavement. It's as if someone sat down, made of formula of what a park needs, and set out to make an overly efficient open space. What you are left with just the idea of a park. This is a 'must see' location purely for the experience of the design. At the time of its construction in 1898, the Old Colony Railroad Bridge was the largest rolling drawbridge of its kind, and ran from Boston to Provincetown. In addition, stones are arranged in a seating pattern to mimic a circular configuration of another bridge that occupied a nearby site. Cabot Cove is accessible via a pedestrian bridge built into the Old Colony Railroad Bridge and along the west side of the Broadway Bridge.

Boston’s Summer Street Bridge, which spans the Fort Point Channel, has been in service since 1899. Originally a drawbridge with rail lines only, it was renovated in 1900 to support road traffic and pedestrians. This update to the bridge rendered the Mount Washington Bridge obsolete, which was removed at that time. Today, the structure currently maintains a fixed position and supports four traffic lanes to and from the city.