Belle Grove Plantation is a late-18th-century plantation house and estate in the northern Shenandoah Valley of Virginia, USA. It is situated in Frederick County, about a mile southwest of Middletown. Built between 1794 and 1797, the large Federal-style manor house is a National Historic Landmark and was opened to the public by its owners, the National Trust for Historic Preservation (NTHP), as a historic house museum in 1967. In 2002, Belle Grove became part of the Cedar Creek and Belle Grove National Historical Park, a National Park Service unit, although it continues to be owned and operated by the NTHP.