On July 1, 1863, Confederate forces outflanked the Union right at Barlow’s Knoll, causing the Union 11th Corps to collapse and retreat through Gettysburg. From near Pennsylvania College, Lt. Louis Fischer observed thousands of Confederate troops advancing and enveloping the Union line. As Confederates pushed forward, Union soldiers fled toward town under intense pressure. During the retreat, Capt. Frederick Von Fritsch narrowly escaped capture and reached Cemetery Hill. Fischer and his engineers also withdrew, avoiding heavy fire while crossing Stevens Run and continuing the retreat through Gettysburg.