Boston Navy Yard Commissioned in 1801, the Boston Navy Yard is one of the United States Navy’s oldest shipbuilding facilities. Formerly known as the Charleston Navy Yard, the facility was in continuous operation through 1974. The facility was purchased by the federal government in 1801 and commissioned to build six warships, including the USS Independence, in an effort to form a state of the art naval armament capable of protecting America. The site built few ships between the years of 1812 and the Civil War, but those commissioned were prestigious. For instance, the Charlestown Navy Yard originally built the USS Merrimack, which later became the CSS Virginia. Other ships of note built by the facility include the USS Cumberland, coincidentally destroyed in battle by the CSS Virginia, and the USS Monadnock, which holds the designation of being one of the few monitors to be constructed entirely at a U.S. Navy Shipyard. Instrumental in solidifying the U.S. Navy as one of the world’s most capable naval forces, the Charlestown Navy Yard was responsible for the construction of over 200 warships during its 174 year history. The facility was also able to maintain and repair thousands of other ships thanks to the Charleston Naval Dry Dock, one of the first of its kind in the Western Hemisphere. The docks were built between 1827 and 1833, and have served the United States Navy for over 100 years. The Civil War brought rapid expansion to the Charlestown Navy Yard. In addition to providing support and maintenance to ships blocking the Southern harbors, the Charleston Navy Yard was responsible for the conversion of smaller ships into warships. Expansion continued and in the 1890s, and the facility began using steel in its ships construction. Now referred to as the Boston Navy Yard, the facility was officially renamed in 1945. The Boston Navy Yard was a vital component of the First and Second World Wars. During World War II, ship building operations required as many as 50,000 employees, working in around the clock, in shifts, seven days a week. After the war, the facility worked to modernize ships that served in World War II. By 1974, however, with work scarce, the Boston Navy Yard became part of the Boston National Historic Park. Today, the site is maintained by the National Park Service and contains such living history as the USS Cassin Young and “Old Ironsides,” the USS Constitution.