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. It is bounded by Battery Place on the north, 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 old 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 as well as boat launches to the Statue of Liberty National Monument. The park and surrounding area is named for the artillery batteries that were built in the late 17th century to protect the settlement behind them. By the 1820s, the Battery had become an entertainment destination, with the conversion of Castle Clinton into a theater venue. During the mid-19th century, the modern-day Battery Park was constructed and Castle Clinton was converted into an immigration and customs center. The Battery was commonly known as the landing point for immigrants to New York City until 1890, when the Castle Clinton immigration center was replaced by one on Ellis Island. Castle Clinton then hosted the New York Aquarium from 1896 to 1941. In 1940, the entirety of Battery Park was closed for twelve years due to the construction of the Brooklyn–Battery Tunnel and the Battery Park Underpass. The park reopened in 1952 after a renovation, but then subsequently went into decline. The Battery Conservancy, founded in 1994 by Warrie Price, underwrote and funded the restoration and improvement of the once-dilapidated park. In 2015, the Conservancy renamed the park to its historic name of "the Battery".