American Battlefield Trust’s map of the Battle of Fisher’s Hill
The Union VI and XIX Corps advanced on September 21, driving back skirmishers and capturing Flint Hill just west of the Manassas Gap Railroad, an elevation overlooking the entire Confederate position. On the 22nd, Crook’s VIII Corps attacked about 4:00 p.m. Brig. Gen. Lunsford Lomax’s cavalry offered little resistance, and the startled infantry were unable to face Crook's attacking force. The Confederate defense collapsed from west to east as Sheridan’s other corps joined in the assault along the Valley Pike.