Directions from Baltimore: Take I295 South (BW Parkway) through DC until it ends. Then take I95 South and cross the Woodrow Wilson Bridge to Virginia. Take the 1st exit after crossing the bridge to RT 1 North (Exit 177B) toward Alexandria. Go about 6 blocks and make a Right on Franklin St. then a Right on South Washington St. Go 8 miles to Mt. Vernon and park in the lot. Note South Washington St name changes to George Washington Memorial Highway.
After Hike, optional Lunch in the Fish Market in Old Town Alexandria. Directions from Mt. Vernon: Follow George Washington Memorial Highway back the same way you came for about 8.5 miles. Make a right at King Street until it ends in a T at Union St. Fish Market is on King Street next to the intersection of King and Union Streets. Parking can be tricky, so it may be better to make a right at Gibbons or Wilkes St, find parking a few blocks from the water and walk to the Fish Market on Union St.
After lunch, a lieserly stroll through historic Old Town to shop and view the Christmas decorations.
Hike: Easy 6 miles on a paved trail that is flat and has nice overlooks on the Potomac River.