
The original Mason-Dixon Line
The 'Mason–Dixon Line' (or "Mason and Dixon's Line") is a demarcation line between four
U.S. states, forming part of the borders of
Pennsylvania,
Maryland,
Delaware, and
West Virginia (then part of
Virginia). It was surveyed between 1763 and 1767 by
Charles Mason and
Jeremiah Dixon in the resolution of a border dispute between
British colonies in
Colonial America. Popular speech, especially since the
Missouri compromise of 1820 (apparently the first official usage of the term "Mason's and Dixon's Line"), uses the Mason-Dixon line symbolically as a cultural boundary between the
Northern United States and the
Southern United States (
Dixie).
Maryland and Pennsylvania both claimed the land between the 39th and 40th parallels according to the charters granted to each colony. The 'Three Lower Counties' (Delaware) along
Delaware Bay moved into the Penn sphere of settlement, and later became the
Delaware Colony, a satellite of Pennsylvania.
In 1732 the proprietory governor of Maryland,
Charles Calvert, 5th Baron Baltimore, signed an agreement with
William Penn's sons which drew a line somewhere in between, and also renounced the Calvert claim to Delaware. But later Lord Baltimore claimed that the document he signed did not contain the terms he had agreed to, and refused to put the agreement into effect. Beginning in the mid-1730s, violence erupted between settlers claiming various loyalties to Maryland and Pennsylvania. The border conflict between Pennsylvania and Maryland would be known as
Cresap's War.
The issue was unresolved until the Crown intervened in
1760, ordering
Frederick Calvert, 6th Baron Baltimore to accept the 1732 agreement. As part of the settlement, the Penns and Calverts commissioned the English team of
Charles Mason and
Jeremiah Dixon to
survey the newly established boundaries between the
Province of Pennsylvania, the
Province of Maryland,
Delaware Colony and parts of
Colony and Old Dominion of Virginia.
After Pennsylvania abolished slavery in 1781, the western part of this line and the
Ohio River became a border between free and slave states, although Delaware remained a slave state.
Geography

Diagram of the survey lines creating the Mason-Dixon Line and "
The Wedge."
Mason and Dixon's actual survey line began to the south of
Philadelphia, Pennsylvania, and extended from a
benchmark east to the
Delaware River and west to what was then the boundary with western Virginia.
The surveyors also fixed the boundary between
Delaware and
Pennsylvania and the approximately north–south portion of the boundary between
Delaware and Maryland. Most of the Delaware–Pennsylvania boundary is a
circular arc, and the Delaware–Maryland boundary does not run truly north-south because it was intended to bisect the
Delmarva Peninsula rather than follow a meridian.
The Maryland–Pennsylvania boundary is an east-west line with an approximate mean latitude of N 39º 43' 20" (
Datum WGS 84). In reality, the east-west Mason-Dixon line is not a true line in the geometric sense, but is instead a series of many adjoining lines, following a path between latitude N 39º 43' 15" and N 39º 43' 23". As such, the line approximates a segment of a
small circle upon the surface of the
(also approximately) spherical Earth. An observer standing on such a line and viewing its path toward an unobstructed horzion, would perceive it to bend away from his line of sight, an effect of the inequality between the amount of curvature to his left and right. Among parallels of latitude, only the
Equator is a
great circle and would not exhibit this effect.
The surveyors also extended the boundary line to run between Pennsylvania and colonial western Virginia, which became
West Virginia after the
American Civil War, though this was contrary to their original charter; this extension of the line was only confirmed later (see
Yohogania County for details).
The Mason–Dixon Line was marked by stones every mile and â€crownstones†every five miles. The stone was shipped from England. The Maryland side says (M) and the Delaware and Pennsylvania sides say (P). Crownstones include the two coats-of-arms. Today, while a number of the original stones are missing or buried, many are still visible, resting on public land and protected by iron cages.
Mason and Dixon confirmed earlier survey work which delineated Delaware's southern boundary from the Atlantic Ocean to the â€Middle Point†stone. They proceeded nearly due north from this to the Pennsylvania border.
Later the line was marked in places by additional benchmarks and survey markers. The lines have been resurveyed several times over the centuries without substantive changes to Mason and Dixon's work. The stones may be a few to a few hundred feet east or west of the point Mason and Dixon thought they were; in any event, the line drawn from stone to stone forms the legal boundary.
According to Dave Doyle at the National Geodetic Survey, part of NOAA, the corner of PA-MD-DE at The Wedge is Boundary Monument #87. The marker â€MDP Corner†dates from 1935 and is offset on purpose.
Doyle said the Maryland–Pennsylvania Mason–Dixon Line is exactly:
: 39° 43′ 19.92216″ N
and Boundary Monument #87 is on that parallel, at:
: 075° 47′ 18.93851″ W.
Visitors to the tripoint are strongly encouraged to first obtain permission from the nearest landowner.
History

A "crownstone" boundary monument on the Mason-Dixon Line. The coat of arms of Maryland's founding
Calvert family is shown. On the other side are the arms of
William Penn.
The line was established to end a boundary dispute between the British colonies of Maryland and Pennsylvania/Delaware. Due to incorrect maps and confusing legal descriptions, the royal charters of the three colonies overlapped. Maryland was granted the territory north of the
Potomac River/
Watkins Point up to the fortieth parallel; Pennsylvania was granted land extending northward from a point "12 miles north of
New Castle Towne," which is located below the fortieth parallel. The most serious problem was that the Maryland claim would put
Philadelphia, which became the major city in Pennsylvania, within Maryland. A protracted legal dispute between the
Calvert family, which controlled Maryland, and the
Penn family, which controlled Pennsylvania and the "Three Lower Counties" (Delaware), was ended by the 1750 ruling that the boundary should be fixed as follows:
★ Between Pennsylvania and Maryland:
★
★ The parallel (latitude line) fifteen miles south of the southernmost point in Philadelphia, measured to be at about 39° 43' N and agreed upon as the Maryland–Pennsylvania line.
★ Between Delaware and Maryland:
★
★ The existing east-west
Transpeninsular Line from the
Atlantic Ocean to its mid-point to the
Chesapeake Bay.
★
★ A
Twelve Mile (radius) Circle around the city of New Castle, Delaware.
★
★ A "Tangent Line" connecting the mid-point of the Transpeninsular Line to the western side of the Twelve-Mile Circle.
★
★ A "North Line" along the meridian (line of longitude) from the tangent point to the Maryland Pennsylvania border.
★
★ Should any land within the Twelve-Mile Circle fall west of the North Line, it would remain part of Delaware. (This was indeed the case, and this border is the "Arc Line.")
The disputants engaged an expert British team, astronomer
Charles Mason and surveyor
Jeremiah Dixon, to survey what became known as the Mason–Dixon Line.
The Mason–Dixon "line" is actually made up of four segments corresponding to the terms of the settlement: Tangent Line, North Line, Arc Line, and 39° 43' N parallel. The most difficult task was fixing the Tangent Line, as they had to confirm the accuracy of the Transpeninsular Line mid-point and the Twelve-Mile Circle, determine the tangent point along the circle, then actually survey and monument the border. They then surveyed the North and Arc Lines. They did this work between 1763 and
1767. This actually left a small
wedge of land in dispute between Delaware and Pennsylvania until
1921.
In April 1765 Mason and Dixon began their survey of the more famous Maryland-Pennsylvania line. They were commissioned to run it for a distance of five degrees of longitude west from the Delaware River, fixing the western boundary of Pennsylvania (see the entry for
Yohogania County). However, in October 1767 at
Dunkard Creek near
Mount Morris, Pennsylvania, nearly 244 miles (392 km) west of the Delaware, a group of
Native Americans forced them to quit their progress. In 1784, surveyors
David Rittenhouse and
Andrew Ellicott and their crew completed the survey of the Mason-Dixon line to the southwest corner of Pennsylvania, five degrees from the Delaware River. Other surveyors continued west to the
Ohio River. The section of the line between the southwestern corner of Pennsylvania and the river is the county line between
Marshall and
Wetzel counties, West Virginia.
The boundary between Pennsylvania and Maryland was resurveyed in
1849, then again in
1900.
The
Missouri Compromise of 1820 created the political conditions which made the Mason-Dixon Line important to the history of slavery. It was during the Congressional debates leading up to the compromise that the term "Mason-Dixon line" was first used to designate the entire boundary between free states and slave states.
On
November 14,
1963, during the bicentennial of the Mason–Dixon Line, U.S. President
John F. Kennedy opened a newly completed section of
Interstate 95 where it crossed the Maryland-Delaware border. It was his last public appearance before the one 8 days later in
Dallas, Texas, where
he was assassinated. The Delaware Turnpike and the Maryland portion of the new road were each later designated as the
John F. Kennedy Memorial Highway.
As a cultural boundary

'Modern definition' The states in dark red are almost always included in modern day definitions of the South, while those in medium red are usually included. The striped states are sometimes/occasionally considered Southern. Note that the Mason-Dixon line forms part of the northern boundary of the striped states
[1][2]
The Mason-Dixon line became symbolic of the division between the "free states" and "slave states" from the
Missouri Compromise until the end of the
American Civil War.
Pennsylvania abolished slavery early while Maryland,
Delaware,
Kentucky, and
Missouri remained
slave states until the end of the war.
After the Civil War, the line continued to be thought of as a cultural boundary, which is imagined as continuing westward from Pennsylvania down the
Ohio River to the
Mississippi River, and crossing the Mississippi to place
Arkansas,
Louisiana and
Texas south of the line. Debate respectfully proceeds as to whether
border states such as
Missouri,
Kentucky,
Maryland and
West Virginia belong on the north or south side of this boundary line.
Cultural references
;Literature
★
Thomas Pynchon wrote a historical novel about the construction of the Mason-Dixon Line entitled ''
Mason & Dixon'', first published in
1997. This book makes no claim of being historically rigorous.
★
George MacDonald Fraser referred to the Mason-Dixon Line in the 1994 novel
Flashman and the Angel of the Lord. This contains the obvious error of referring to the Line's latitude as 39' 43" instead of 39º 43'.
;Film
★ The animated short film "
Southern Fried Rabbit" (released
May 2,
1953) features
Bugs Bunny and
Yosemite Sam and takes place on the Mason-Dixon Line — literally, ''on'' it. The cartoon depicts the north as being barren and empty, while the south is lush and green.
★ In the film
Pulp Fiction (first released on
October 14,
1994), Butch Coolidge (
Bruce Willis) and Marcellus Wallace (
Ving Rhames) are captured and imprisoned in ''The Mason-Dixon Pawnshop''.
★
Antonio Tarver plays a character in the 2006 movie ''
Rocky Balboa'' named Mason "The Line" Dixon.
★ In the children's film, Little Big League, the announcer rambles off unimportant facts, mentioning that the Angels have been the best team this year away "north of the Mason-Dixon line".
;Television
★ In several episodes of the
American television series ''
In the Heat of the Night'', a roadhouse in
Sparta, Mississippi is called ''Mason's Dixieline''.
★ In the
Family Guy episode "
To Live and Die in Dixie"
Peter Griffin refers to the border as the
Donna Dixon Line.
★ In
Viva La Bam during the Civil War Re-enactment episode,
Bam pours white chalk on
Don Vito and calls it the "Mason Dixon" line for their re-enactment.
;Music
★ The song ''
Rock-a-Bye Your Baby with a Dixie Melody'', most famously recorded by
Al Jolson, contains the lines "Just hang my cradle, Mammy mine,/Right on that Mason Dixon line/And swing it from Virginia/To Tennessee with all the love that's in ya."
[1]
★ The
Johnny Cash tune "
Hey Porter" has the singer asking the railroad how long it will be until the train crosses the Mason-Dixon Line, as he is longing to be back in the
South.
★ The popular song "Are You From Dixie?" written by
Jack Yellen and
George L. Cobb in 1915 and recorded by many country artists over the years, including the
Blue Sky Boys in the 1930s and
Jerry Reed more recently, references some states south of the Mason-Dixon-Line.
★
Mark Knopfler and
James Taylor sing about the construction of the Mason-Dixon Line in "
Sailing to Philadelphia (Sailing to Philadelphia, Mercury Records,
2000)" Knopfler was inspired by Pynchon's book.
★
Waylon Jennings &
Mel Tillis also have a song out titled "Mason Dixon Lines" that references the line in every verse.
★ The musical group
Virginia Coalition have a song titled "Mason-Dixon" that makes reference to the historical line.
★ The satirist
Tom Lehrer mentions the Mason-Dixon line in the song "I Wanna Go Back to Dixie"
★ The politically charged band
Rage Against the Machine have a reference to "the new line of Mason-Dixon" in the song "Maria" off the album ''
The Battle of Los Angeles''.
★ The song "Southern Girl" by
Maze contains the lyrics: "...below the Mason-Dixon line / down there where the girls are fine / Sure know how to treat me you just make me feel so good / Southern girl here's to you no one can do it like you do."
★ The Country band
Lady Antebellum have a song called "Mason Dixon Line" that references the line in the lyrics: "...Mama said home is where the heart is / Just south of the Mason Dixon Line..."
★ Christian metalcore band
Norma Jean, at one of their live performances, dedicated their song "Memphis Will Be Laid To Waste" to "everyone south of the Mason-Dixon line...and everyone north of it too."
References
1. UNC-CH surveys reveal where the ‘real’ South lies David Williamson
2. http://www.pfly.net/misc/GeographicMorphology.jpg
The song "Guillotine (Swordz)" from the album "Only built 4 cuban linx" By the artist Raekwon of the Wu Tang Clan features the closing lines "''the Land of the Lost/ Notorious henchman from the North/ Strikin niggaz where the Mason-Dixon line crossed''."
External links
★
The Mason-Dixon Line also is the southern border of Pennsylvania with West Virginia. Visit locations and see photos from sites along The Line near its western end at the southwest corner of Pennsylvania.
★
Mason-Dixon Line
★
History of the Mason-Dixon Surveys
★
The Charter of Maryland (1632)
★
Charter for the Province of Pennsylvania (1681)
★
Evolution of the Mason-Dixon Line
★
The Evolution of the Mason and Dixon Line - facsimile copy of this 1902 text available on-line at Penn State's Digital Bookshelf
★
HyperArts' ''Mason & Dixon'' Web Guide & Concordance
Books
★ Danson, Edwin. ''Drawing the Line: How Mason and Dixon Surveyed the Most Famous Border in America''. Wiley. ISBN 0-471-38502-6.