Germantown Academy, informally known as GA and originally known as the Union School, is the oldest nonsectarian day school in the United States. The school was founded on December 6, 1759, by a group of prominent Germantown citizens in the Green Tree Tavern on the Germantown Road. Germantown Academy enrolls students from pre-kindergarten to 12th grade and is located in the Philadelphia suburb of Fort Washington, having moved from its original Germantown campus in 1965. The original campus (see Old Germantown Academy and Headmasters' Houses) is listed on the National Register of Historic Places. The school shares the oldest continuous high school football rivalry with the William Penn Charter School.