 While trying to elude Union cavalry, John Wilkes Booth and David Herold crossed into the county from Maryland on April 21, 1865 after assassinating US president Abraham Lincoln.Booth and Herold landed at the mouth of Gambo Creek, before meeting with Confederate agents, who guided their passage to Port Conway, where they would cross into Port Royal, in Caroline County, Virginia.According to the U.S. Census Bureau, the county has a total area of , of which is land and (4.3%) is water.