The Potomac Heritage Trail, also known as the Potomac Heritage National Scenic Trail or the PHT, is a designated National Scenic Trail corridor spanning parts of the mid-Atlantic region of the United States that will connect various trails and historic sites in Virginia, Maryland, Pennsylvania, and the District of Columbia. The trail network includes 710 miles (1,140 km) of existing and planned sections, tracing the natural, historical, and cultural features of the Potomac River corridor, the upper Ohio River watershed in Pennsylvania and western Maryland, and a portion of the Rappahannock River watershed in Virginia. The trail is managed by the National Park Service and is one of three National Trails that are official NPS units. (Ref: https://en.wikipedia.org/wiki/Potomac_Heritage_Trail)