 The fleeing assassin galloped into southern Maryland , accompanied by David Herold , having planned his escape route to take advantage of the sparsely settled area 's lack of telegraphs and railroads , along with its predominantly Confederate sympathies . He thought that the area 's dense forests and swampy terrain of Zekiah Swamp made it ideal for an escape route into rural Virginia . At midnight , Booth and Herold arrived at Surratt 's Tavern on the Brandywine Pike , 9 miles ( 14 km ) from Washington , where they had stored guns and equipment earlier in the year as part of the kidnap plot . 
