Gen. Jacob Cox, Union Ninth Corps
After finally driving the Confederates from the bluffs overlooking the Lower Bridge, close to 10,000 Federal troops crossed Antietam Creek and formed on the ridge 300 yards to the east (behind you). At approximately 3:00 p.m., a mile-wide battle line of Union soldiers swept forward across the extremely rugged terrain. About 2,500 Confederate soldiers and forty cannon awaited their advance.
Burnside's men moved through a withering fire of artillery and infantry, surging to the high ridge to the west (in front of you). At about 4:00 p.m., the last of Lee's Confederate reinforcements arrived on the field (from your left). Although exhausted and footsore after marching seventeen miles from Harpers Ferry, Gen. A.P. Hill's Confederate soldiers slammed into the exposed Union left flank and drove them back. As darkness fell, the battlefield finally grew quiet. One soldier in the Ninth Corps remembered, "The conflict died away, the enemy also had got all the fighting they wanted for the day. It had been an afternoon in the valley of death."