Washington & Old Dominion Railroad Trail 
21293 Smiths Switch Rd.
Ashburn, VA 20147
703-729-0596
http://www.nvrpa.org/park/w_od_railroad/
Park: Bike, Hike, Horse, Picnic, Walk
The 100-foot-wide W&OD has been called “the skinniest park in Virginia.” But it is also one of the longest parks, 45 miles of paved trail for walking, running, bicycling and skating and 32 miles of adjacent gravel trail for horseback riding. Built on the roadbed of the former Washington & Old Dominion Railroad, the multi-use W&OD Trail runs through the urban heartland and countryside of Northern Virginia.