Mason-Dixon Line Ran Through Pa.

Few people realize that surveying for the Mason-Dixon Line started at a tiny house on the southern edge of Philadelphia.

The house is long gone, but its location was recently discovered by group of Pennsylvania college students paging through centuries-old property records. State officials approved a historical marker for the site last month.

The finding comes as the nation marks the 150th anniversary of the start of the Civil War. The Mason-Dixon Line has become synonymous with the divide between North and South, but that obscures its true origin.

Charles Mason and Jeremiah Dixon began their survey a century earlier to settle a border dispute between Pennsylvania and Maryland.

The 250th anniversary of the Mason-Dixon Line is in 2013.