In the spring of 1863, Confederate Gen. Robert E. Lee began the march of the Army of Northern Virginia through the Shenandoah Valley toward the campaign that culminated at Gettysburg. At Winchester, ninety-six hundred Federals under Gen. Robert H. Milroy blocked the route, so Lee sent Gen. Richard S. Ewell’s 2nd Corps to clear the way. After Confederates attacked Winchester on June 14, 1863, Milroy realized his command was in danger of being surrounded and evacuated the city during the night. Anticipating this, Ewell ordered Gen. Edward Johnson’s division to block the Union escape route to Harper’s Ferry. Before dawn, Johnson, with only Gen. George H. Steuart’s brigade and two cannon from the 1st Maryland Battery, struck the Federals while moving west and took positions along the railroad tracks as Lt. Col. Snowden Andrews placed the guns at the bridge. Federal forces repeatedly tried to seize the bridge and open the road, and the Confederate line nearly collapsed before reinforcements arrived and additional Southern artillery was placed on the high ground. After the final Federal repulse, Lt. C.S. Contee reported to Andrews that he had only a sergeant and two men left at the bridge, with thirteen of the sixteen artillerists killed or wounded. Lee called the stand at the bridge “the Thermopylae of my campaign.” The 13th Pennsylvania Cavalry also suffered heavily when Southern artillery found its range as the unit shifted position to charge, and 334 of its 655 men became casualties. Milroy escaped capture, but nearly half his troops did not, and Lee crossed the Potomac River with 23 newly captured cannon and supplies. The clash also touched divided families, including the Culps of Gettysburg: Wesley Culp, who had moved to Virginia and joined the South, and his brother William, who served in the Union army, both fought there; William survived the war, while Wesley was later killed at Gettysburg near a hill named for his ancestors.