 By early March 1862 Major General McClellan's advance on the Peninsula was bringing pressure on the Confederate Army of the Potomac to pull back from Centreville, Virginia, who just happened to be using six miles (10 km) of the B&O's rail bars that had been seized in this raid and stored in Winchester, Virginia.The Great Train Raid bounty had supplied the Confederate Army with the materials to build the Centreville Military Railroad, where Captain Sharp was once again managing much of the effort.After Centreville was abandoned and the lower Shenandoah Valley was left lightly defended, the B&O Railroad came under Federal control, and B&O work crews were able to repair bridges and lay track during the entire month of March.