Castle Williams was completed in 1811. It was designed and erected between 1807 and 1811 and was named after Lt. Col. Jonathan Williams of the U.S. Army Corps of Engineers. Castle Williams is a red sandstone, circular, defensive construction on the West Point of Governors Island and is considered a prototype for new types of coastal fortification. Castle Williams has served different purposes over the years - a fortification, a prison, a youth community center with a nursery and meeting rooms for Scouts and clubs, a woodworking shop, art studios, a photography laboratory, and a museum. The late '70s brought another change and the fort became the groundskeeping shop for the Coast Guard base. Castle Williams was listed in the National Register of Historic Places on July 31, 1972.