July 1. The First and Eleventh Corps arrived, and were engaged north, and, west of Gettysburg,and fell back to Cemetery Hill in rear of the town. The Twelfth Corps and a large part of the Third Corps arrived at the close of the day.

July 2 . The remainder of the Third Corps and the Fifth and Second Corps arrived in the morning. The Sixth Corps late afternoon. The Third Corps having advanced was attacked by Longstreet's Confederate Corps and Anderson's Division of Hill's Corps. The Fifth Corps, and the First Division of the Second Corps going to the support of the Third Corps an engagement ensued until nightfall when the Union forces had been driven back from their advanced position and the Confederates repulsed.

July 3. The Twelfth Corps having by order vacated a large part of its line on Culps Hill, on the night of the 2d and Johnson's Division of Ewell's Corps having occupied the works. The Twelfth Corps in the morning attacked and regained the lines it had previously vacated. Hill's Corps and Pickett's Division of Longstreets Corps in the afternoon attacked the line of the Second Corps and were repulsed with great Loss. Stuart's Confederate Cavalry in the afternoon attacked the Second Cavalry Division and the Second Brigade Third Cavalry Division and was repulsed.

From the marker:

Headquarters of
Major General
George G. Meade
Commanding
Army of the Potomac

Headquarters monument to the Army of the Potomac

see enlargement of monument (above)
or enlargement of marker (below)

Hedquarters marker for George Meade at Gettysburg