On July 4, 1863, following three days of battle at Gettysburg, the two armies watched each other from opposing ridges. The Union commander, General George G. Meade, sent out skirmishers to probe the Confederate lines. But no order was given to attack. Meade knew the Confederates would be hard to dislodge from a defensive position. The Confederate army would probably have welcomed an attack so as to repay their terrible losses they suffered the day before. But Lee's main concern was getting his army and their captured supplies back to Virginia. Lee knew it was extremely dangerous to retreat in front of an enemy army. Lee gave detailed instructions on how the retreat would be accomplished. The Confederate Army of Northern Virginia was to hold its position on Seminary Ridge all day on July 4th. The more than 10,000 wounded men would be moved by wagon train to Williamsport and cross the Potomac to Virginia.