 Schenck took six companies over the Alexandria, Loudon and Hampshire Railroad line, dropping off detachments to guard railroad bridges between Alexandria, Virginia and Vienna, Virginia.As the train approached Vienna, about north of Fairfax Court House and from Alexandria, 271 officers and men remained with the train.On the same day, Confederate States Army Col. Maxcy Gregg took the 6–month 1st South Carolina Infantry Regiment, about 575 men, two companies of cavalrymen (about 140 men) and a company of artillery with two artillery pieces (35 men), about 750 men in total, on a scouting mission from Fairfax Court House toward the Potomac River.