Mason–Dixon line

The Mason-Dixon line is a survey boundary that was originally established in the 18th century to resolve a border dispute between the British colonies of Maryland and Pennsylvania. Surveyors Charles Mason and Jeremiah Dixon carried out the survey from 1763 to 1767. The line runs approximately along the latitude of 39°43′ N and came to symbolize the cultural division between the Northern and Southern U.S. states, particularly during the period leading up to the Civil War.