Between 1763 and 1768, British astronomers Charles Mason and Jeremiah Dixon surveyed what is now the northern border of Maryland and the southern border of Pennsylvania, the State Line. Each mile they would place a stone marker, one side having a P for Pennsylvania, and the other side with a M for Maryland. Every five miles along the line they placed a "crown-stone." The crown stone displayed the coat of arms of Lord Baltimore on the south side, and The Penns on the north side (see stone below, second from bottom). The stones were imported from England and are still in place today!
The Mason Dixon Line later became the line separating slave states (Maryland) and free states (Pennsylvania), or the line between North and South during the Civil War. Runaway slaves would try to make it north of the Mason Dixon Line to freedom. Then they would continue their journey, via safe houses in southern Pennsylvania (part of the Underground Railroad), farther north.
|Near an I-81 exit at the state line, I found one of the original mile markers. The P indicates I am on the Pennsylvania side.|
A modern marker near the mile stone (above).
|Near the mailbox at the right in the picture is one of the crown stones, placed every 5 miles along the Mason Dixon Line. This stone happens to be the 100th mile along the Mason Dixon Line. To the left is Maryland.|
|The coat of arms of Lord Baltimore is still visible on the Maryland side of the crown stone, The house is in Pennsylvania.|