The King William County Courthouse is a courthouse located in the town of King William, King William County, Virginia. The original courthouse structure was constructed in 1725; it is the oldest courthouse building in continuous use in the United States. The courthouse is constructed of brick laid in Flemish bond. In 1840 the courthouse was enlarged and a brick wall was erected to enclose the court green and to keep livestock and poultry away from the buildings. A new courthouse complex has been constructed to augment the old; however, hearings are still held in the old building to preserve its historic designation.It was listed on the National Register of Historic Places in 1969.
