The Ambrose lightship was built in 1908 to guide ships safely from the Atlantic Ocean into the broad mouth of lower New York Bay between Coney Island, New York and Sandy Hook, New Jersey—an area filled with sand bars and shoals invisible to approaching vessels. While a lighthouse is normally used for this purpose, the water here was too deep, and the bottom too soft, and this floating alternative was devised. South Street's Ambrose lightship occupied her original station until 1933, and then served as the Scotland lightship closer to Sandy Hook until 1963. She was given to the museum by the U.S. Coast Guard in 1968. Today, visitors can board the Ambrose to view an exhibition of photographs, charts, and artifacts on navigation and the role of lightships.