Pennsylvania–Delaware border

E682505

interstate border state boundary

The Pennsylvania–Delaware border is the state line separating Pennsylvania and Delaware, historically notable for its role in colonial boundary disputes and its distinctive arc-shaped segment centered on New Castle.

Try in SPARQL Jump to: Surface forms Disambiguation Statements Elicitation Referenced by

All labels observed (6)

Label	Occurrences
Delaware–Pennsylvania state line	3
Pennsylvania state line	3
Delaware state border	2
Delaware–Pennsylvania border	1
Pennsylvania–Delaware border canonical	1
Pennsylvania–Delaware state line	1

How this entity was disambiguated

This entity first appeared as the object of triple T7712905 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.

NED1 Entity disambiguation (via context triple) gpt-5-mini-2025-08-07

Target entity: Pennsylvania–Delaware border
Context triple: [Chadds Ford, Pennsylvania, locatedNear, Pennsylvania–Delaware border]

A. Pennsylvania–New York border
The Pennsylvania–New York border is the interstate boundary separating the U.S. states of Pennsylvania and New York, running largely east–west across the northern edge of Pennsylvania.
B. Pennsylvania border
The Pennsylvania border is the state boundary line separating Pennsylvania from its neighboring states, including West Virginia near Wheeling.
C. Maryland state line
The Maryland state line is the boundary separating the state of Maryland from its neighboring states, including Pennsylvania’s Bedford County.
D. District of Columbia–Maryland border
The District of Columbia–Maryland border is the boundary line separating Washington, D.C. from the state of Maryland, running through both urban and natural areas in the region.
E. Virginia–West Virginia boundary
The Virginia–West Virginia boundary is the state line that separates Virginia from its northwestern neighbor West Virginia, following a historically contested course through the Appalachian region.
F. None of above. chosen
G. Unsure - the case is ambiguous/there is not enough information to decide.

NED2 Entity disambiguation (via description) gpt-5-mini-2025-08-07

Target entity: Pennsylvania–Delaware border
Target entity description: The Pennsylvania–Delaware border is the state line separating Pennsylvania and Delaware, historically notable for its role in colonial boundary disputes and its distinctive arc-shaped segment centered on New Castle.

A. Pennsylvania–New York border
The Pennsylvania–New York border is the interstate boundary separating the U.S. states of Pennsylvania and New York, running largely east–west across the northern edge of Pennsylvania.
B. Pennsylvania border
The Pennsylvania border is the state boundary line separating Pennsylvania from its neighboring states, including West Virginia near Wheeling.
C. Maryland state line
The Maryland state line is the boundary separating the state of Maryland from its neighboring states, including Pennsylvania’s Bedford County.
D. District of Columbia–Maryland border
The District of Columbia–Maryland border is the boundary line separating Washington, D.C. from the state of Maryland, running through both urban and natural areas in the region.
E. Virginia–West Virginia boundary
The Virginia–West Virginia boundary is the state line that separates Virginia from its northwestern neighbor West Virginia, following a historically contested course through the Appalachian region.
F. None of above. chosen

Statements (42)

Predicate	Object
instanceOf	interstate border ⓘ state boundary ⓘ
adjacentTo	Chester County, Pennsylvania ⓘ Delaware County, Pennsylvania ⓘ New Castle County, Delaware ⓘ
approximateArcRadius	12 miles ⓘ
cartographicallyDistinct	yes ⓘ
centerOfArc	New Castle, Delaware ⓘ
country	United States ⓘ linked to: United States of America
definedBy	Twelve-mile radius from New Castle courthouse ⓘ colonial charters of Pennsylvania and Delaware ⓘ
governingAuthorityAtCreation	British Crown ⓘ
hasCoordinateSystemBasis	surveys conducted in the 18th century ⓘ
hasDisputeType	colonial-era territorial dispute ⓘ
hasLanguage	English (legal descriptions) ⓘ
hasLegalPrecedent	U.S. Supreme Court decisions on Delaware–New Jersey and related boundaries ⓘ
hasNotableFeature	Twelve-Mile Circle ⓘ
hasSegment	arc boundary along the Twelve-Mile Circle ⓘ straight-line boundary segments north of the arc ⓘ
historicalRole	dispute between William Penn and Lord Baltimore land claims ⓘ site of colonial boundary disputes ⓘ
influencedBy	English colonial grants ⓘ royal charters in the 17th and 18th centuries ⓘ
jurisdictionBoundaryFor	Commonwealth of Pennsylvania ⓘ linked to: Pennsylvania State of Delaware ⓘ linked to: Delaware
legalStatus	recognized state boundary in U.S. law ⓘ
mapFeatureType	political boundary ⓘ
notableFor	one of the few circular state boundaries in the United States ⓘ use of a geometric arc rather than only straight lines ⓘ
partOf	border of Delaware ⓘ border of Pennsylvania ⓘ
passesNear	Delaware River ⓘ
relatedEvent	Mason–Dixon survey ⓘ linked to: Survey of the Mason–Dixon line
relatedTo	Mason–Dixon line ⓘ linked to: Mason–Dixon Line
resolvedBy	agreements following Mason–Dixon survey ⓘ
separates	Delaware ⓘ Pennsylvania ⓘ
shapeFeature	arc-shaped segment centered on New Castle, Delaware ⓘ
timePeriodOfFormation	17th–18th centuries ⓘ
usedFor	electoral district delimitation ⓘ law enforcement jurisdiction delimitation ⓘ taxation jurisdiction delimitation ⓘ

How these facts were elicited