Washington & Old Dominion Trail is a hiking, biking, and horse trail in Falls Church City, Loudoun County, Arlington County, and Fairfax County, Virginia. It is within Washington & Old Dominion Regional Park, Benjamin Banneker Park, Raflo Park, Glen Carlyn Park, Washington & Old Dominion Trail Regional Park, Waters And Caffi Fields, Washington and Old Dominion Railroad Regional Park, GlenCarlyn Park, Idylwood Park, Bluemont Park, and Bon Air Park. It is 44.5 miles long and begins at 372 feet altitude. Traveling the entire trail is 9.8 miles with a total elevation gain of 416 feet. The W&OD Trail Parking parking, the Herndon Depot Museum museum, and the W&OD Trail Info information board are near the trailhead. There are also parkings, restrooms, and fountains. Liberty Street Lot, Herndon Municipal Parking Lot, W&OD Trail Parking, Washington & Old Dominion Railroad Regional Park, and other parkings, East Falls Church Metro Parking, Community Center, Four Mile Run Park and Ride, Post Office, Community Center, and other parkings, Democracy Parking Garage, Hotel Parking Garage & Valet, and other parkings, the Friedman House museum, Park Ranger Station and other restroom, Vienna Memorial Fountain and other fountains, the Freeman House Historic Site (elevation 354 feet) attraction, the Park-and-Ride and Park-and-Ride parkings, the Luck Stone Quarry Overlook viewpoint, Sparrow Pond Overlook, Bluemont Junction, The Arlington Mill, Barcroft, Ground Hog, and another information board, the Bluemont Park Ranger Station ranger station, the Washington & Old Dominion Caboose tourism, and the Poplar Heights Recreation Association swimming pool can be seen along the trail. There are also woods, trees, shelters, bbqs, grasslands, picnic sites, tree rows, and beaches along the trail. The trail ends near the Washington and Old Dominion Bike Trail MM Zero information board.