On the morning of June 30, 1863, J.E.B. Stuart led 4,500 Confederate cavalrymen across the Mason-Dixon Line into southern York County, Pennsylvania. He expected to rendezvous with the extreme flank of Robert E. Lee's Army of Northern Virginia somewhere near the Susquehanna River, likely on a line between York and Carlisle. Instead, he unexpectedly encountered a division of enemy cavalry from the Union Army of the Potomac, much farther north than he expected them to be. After a stalemated battle, Stuart skillfully withdrew his troops and began a grueling two-day trek through the hilly countryside in a futile effort to locate Lee's main force. Along the way, his men created calamity for the citizens.