Governors Island is a 172-acre island in the heart of New York Harbor. Yards away from lower Manhattan and Brooklyn, it's easily accessible by ferry and open to the public during the summer.
At the turn of the 19th century, there was a movement in America towards national self-reliance. The young country wanted to solidify its standing as a world power. Lt. Col. Jonathan Williams, grand nephew of Benjamin Franklin, led much of the movement to achieve military self-reliance.
As commandant of the Army Corps of Engineering, Williams was tasked with the improvement of America's Coastal defenses. In 1806 during the creation of the Second American System of Coastal Defense, Williams designed the castle on Governors Island that would be named after him. Though the new system of defenses proved vital in the War of 1812, Castle Williams itself never fired a shot in battle.
By the 1830s new defense technology had surpassed Castle Williams, which was converted into army barracks. It was eventually used as a prison during the American Civil War along with Fort Jay. The castle faced threat of demolition when Governors Island was passed to the United States Coast Guard in 1966. However, it was converted into a youth center and later added to the National Register of Historic Places in 1972.
Today the castle is included in the 22-acre Historic District of Governors Island.
In 2011 the Castle opened its gates to the public for the first time in its history. Its debut followed a two-year restoration that included installations of exhibits highlighting its military history. The courtyard, outdoor exhibits, and all three levels are open for public visitation.