This exhausting but scenic trail connects George Washington's home in Northern Virginia with the Lincoln Memorial in Washington. The path parallels the Potomac River at times and winds its way through lush parks that help you forget how far you're cycling, walking or jogging. Start to finish, it's 18.5 miles and the uneven terrain doesn't make it seem any shorter. Refreshment stands on each end sell drinks and snacks, but once you get past Alexandria, there are long stretches where you can't buy anything. Check your bicycle tires and fill your pockets with energy sources before heading out.
Web site includes a map of the trail.
Where Parallels the Georgw Washington Memorial Parkway in Northern Virginia.