Where the North meets the South, located near Mason Dixon milestone 1, it's in Maryland but very close to Pennsylvania. A small parking area is located about 500' from the cache at the bottom of the hill, just across a branch of the Christina River, on the south side of the road.
The need for the Mason Dixon line began about 200 years before the Civil war began when lands were granted to George Calvert and WIlliam Penn in the mid-1600's. A chief justice in the British court decided a boundary, 15 miles south of Philidelphia, would be established to make it clear which lands where granted to George Calvert (Maryland) and William Penn (Pennsylvania). The 5 year process to mark the line was started in 1763 by Mason and Dixon.