Fort Lyon stood in this vicinity as the major fortification on the left flank of the Federal defenses guarding the city of Washington during the Civil War. Named in honor of Brig. Gen. Nathaniel Lyon, the fort covered an area of nine acres with its forty gun-emplacements. New York, Massachusetts and Ohio troops garrisoned here controlled the Hunting Creek valley, the Little River Turnpike, and the railroad depot as well as the town of Alexandria. On 10 June 1863, President Lincoln personally inspected the damage caused by the spectacular explosion of the fort’s powder magazine.
