Union forces pursue Lee's into Maryland and Stuart's covering Confederates clash with Union cavalry

Confederate General J.E.B. Stuart's cavalry was tasked with holding back the Union pursuit of the Army of Northern Virginia into Maryland after Gettysburg.  With Lee delayed by a flooded Potomac, this mission became critical and a series of cavalry engagements between Stuart and General Judson Kilpatrick's horsemen, usually fighting dismounted as heavy rains made sustained mounted action difficult, were fought around Funkstown and Boonsboro, Maryland. Lee's main force escaped across the Potomac four days later.  (By John Osborne)