W&OD takes its name from the railroad whose tracks ran along the right-of-way from 1859 to 1968, and the scenery along the trail progresses, railroad-like, from high-rise and interstate to backyard single-family suburbia to rolling farmland. The two trails don't intersect, but they come close not far from Leesburg; you can make the Potomac crossing at tiny White's Ferry (301/349-5200; 5 a.m. to 11 p.m. daily, surface permitting). For a helpful trail guide and list of lodgings that are near both paths, send $1 to the Tri-State Bike Trail Group (800/644-1806), or you can download the guide for free at www.norrishouse.com.
This flat, wonderful trail follows a railbed west from Shirlington to Purcellville. The eastern half, however, is heavily traveled, so go west, young men and women, and park at either Leesburg's Loudoun County High School (take Route 7 to a left on Catoctin Circle to another left on Dry Mill Rd.) or Purcellville's Loudoun Valley High School (Route 7 Bypass to a left on Route 278, a right onto Hirst Rd. and a left onto Maple St.). You can park there daily in summer but only on weekends during the school year.
--John Kelly and Craig Stoltz