Statue of Liberty National Monument in the context of "Port of New York and New Jersey"

The Battery, formerly known as Battery Park, is a 25-acre (10 ha) public park located at the southern tip of Manhattan Island in New York City facing New York Harbor. The park is bounded by Battery Place on the north, with Bowling Green to the northeast, State Street on the east, New York Harbor to the south, and the Hudson River to the west. The park contains attractions such as an early 19th-century fort named Castle Clinton; multiple monuments; and the SeaGlass Carousel. The surrounding area, known as South Ferry, contains multiple ferry terminals, including the Staten Island Ferry's Whitehall Terminal; a boat launch to the Statue of Liberty National Monument (which includes Ellis Island and Liberty Island); and a boat launch to Governors Island.

The park and surrounding area are named for the artillery batteries that were built in the late 17th century to protect the fort and settlement behind them. By the 1820s, the Battery had become an entertainment destination and promenade, with the conversion of Castle Clinton into a theater venue. During the mid-19th century, the modern-day Battery Park was laid out and Castle Clinton was converted into an immigration and customs center. The Battery was commonly known as the landing point for immigrants arriving in New York City until 1892, when the immigration center was relocated to Ellis Island in the middle of the harbor. Castle Clinton (sometimes called, Castle Garden) then hosted the New York Aquarium from 1896 to 1941.

In the United States, a national monument is a protected area that can be created from any land owned or controlled by the federal government by proclamation of the president of the United States or an act of Congress. National monuments protect a wide variety of natural and historic resources, including sites of geologic, marine, archaeological, and cultural importance. The Antiquities Act of 1906 gives presidents the power to proclaim national monuments by executive action. In contrast, national parks in the U.S. must be created by Congressional legislation. Some national monuments were first created by presidential action and later designated as national parks by congressional approval.

The 138 national monuments are managed by several federal agencies: the National Park Service, United States Forest Service, United States Fish and Wildlife Service, the Bureau of Land Management, and the National Oceanic and Atmospheric Administration (in the case of marine national monuments). Historically, some national monuments were managed by the War Department.

The Port Authority of New York and New Jersey, (PANYNJ; stylized, in logo since 2020, as Port Authority NY NJ) is a joint venture between the U.S. states of New York and New Jersey, established in 1921 through an interstate compact authorized by the United States Congress. The Port Authority oversees much of the regional transportation infrastructure, including bridges, tunnels, airports, and seaports, within the geographical jurisdiction of the Port of New York and New Jersey. This 1,500-square-mile (3,900 km) port district is generally encompassed within a 25-mile (40 km) radius of the Statue of Liberty National Monument. The Port Authority is headquartered at 4 World Trade Center in Lower Manhattan.

The Port Authority operates the Port Newark–Elizabeth Marine Terminal, which consistently ranks among the largest ports in the United States by tonnage handled, and the largest on the Eastern Seaboard. The Port Authority also operates six bi-state crossings: three connecting New Jersey with Manhattan, and three connecting New Jersey with Staten Island. The Port Authority Bus Terminal and the PATH rail system are also run by the Port Authority, as well as LaGuardia Airport, John F. Kennedy International Airport, Newark Liberty International Airport, Teterboro Airport, and Stewart International Airport. The agency has its own 2,100 member Port Authority Police Department.

The Statue of Liberty (Liberty Enlightening the World), a colossal sculpture on Liberty Island in New York Harbor, underwent an extensive conservation-restoration between 1984 and 1986, in advance of its centennial. The statue, designed by French sculptor Frédéric Auguste Bartholdi, is part of the Statue of Liberty National Monument. International attention to the Statue of Liberty's poor state was called upon the restoration of similarly-built Aimé Millet's Vercingétorix statue in eastern France. Much of the Statue of Liberty restoration effort was based on unprecedented restorative methods, as metallurgical repair work on such a large scale had never been attempted. Many scientists, engineers, government organizations, and professional consultants evaluated and dealt with the various problems and tasks facing the restoration effort.

The restored statue was reopened during Liberty Weekend, its 100-year anniversary celebration held July 3–6, 1986.

Ellis Island is an island in New York Harbor, within the U.S. states of New Jersey and New York. Owned by the U.S. government, Ellis Island was once the busiest immigrant inspection and processing station in the United States. From 1892 to 1954, nearly 12 million immigrants arriving at the Port of New York and New Jersey were processed there; as many as two-fifths of Americans may be descended from these immigrants. It has been part of the Statue of Liberty National Monument since 1965 and is accessible to the public only by ferry. The north side of the island is a national museum of immigration, while the south side of the island, including the Ellis Island Immigrant Hospital, is open to the public through guided tours.

The name derives from Samuel Ellis, a Welshman who bought the island in 1774. In the 19th century, Ellis Island was the site of Fort Gibson and later became a naval magazine. The first inspection station opened in 1892 and was destroyed by fire in 1897. The second station opened in 1900 and housed facilities for medical quarantines and processing immigrants. After 1924, Ellis Island was used primarily as a detention center for migrants. During both World War I and World War II, its facilities were also used by the U.S. military to detain prisoners of war. After the immigration station's closure, the buildings languished for several years until they were partially reopened in 1976. The main building and adjacent structures were completely renovated into a museum in 1990.