the City of Falls Church and travels east to meet the Mount Vernon Trail south of Ronald Reagan Washington National Airport. Washington & Old Dominion Railroad Trail, a paved rail trail that travels northwest from the Arlington County/Alexandria boundary to Purcellville, Virginia (accessed from the Four Mile Run Trail). Rock Creek Park Trail, a paved trail that travels north through Washington, D.C., and Montgomery County, Maryland and ends near Lake Needwood (accessed from the Arlington Memorial Bridge). Chesapeake and Ohio Canal towpath, an unpaved path that travels northwest from Georgetown in Washington, D.C., for to Cumberland, Maryland (accessed from the Francis Scott Key Bridge). Capital Crescent Trail, a paved rail trail that travels south and east from Bethesda, Maryland to Georgetown (accessed from the Francis Scott Key Bridge). Custis Trail, a paved trail that begins in Rosslyn at the end of the Mount Vernon Trail, travels west alongside I-66 and connects to the Washington & Old Dominion Railroad Trail. Northern Extension (Potomac Heritage Trail), a unpaved hiking trail beginning at the end of the Mount Vernon Trail northwest of Theodore Roosevelt Island and traveling northwest through Arlington and Fairfax Counties in and near the Potomac River gorge and near the George Washington Memorial Parkway. The trail travels near the shoreline of the Potomac River, crosses under the Francis Scott Key Bridge and passes Chain Bridge. The trail then travels inland along Pimmit Run, passes Fort Marcy Park, returns to the Potomac's shoreline and passes Turkey Run Park. The trail ends after passing beneath the American Legion Memorial Bridge, which carries the Capital Beltway (Interstate 495) over the Potomac River. Gallery Scenes along the Mount Vernon Trail, from south to north: Notes References External links Video of entire trail north to south Bike paths in Virginia Transportation in Arlington County, Virginia Protected areas of Arlington County, Virginia Protected areas of Fairfax County, Virginia Transportation in Fairfax County, Virginia Protected areas of Alexandria, Virginia Transportation in Alexandria, Virginia Protected areas established in 1972 1972 establishments in Virginia