CSX Old Main Line Subdivision
E430951
The CSX Old Main Line Subdivision is a historic freight rail line in Maryland that traces much of the original route of the Baltimore and Ohio Railroad, one of the oldest railroads in the United States.
All labels observed (3)
| Label | Occurrences |
|---|---|
| CSX Old Main Line Subdivision canonical | 2 |
| Old Main Line Subdivision | 2 |
| CSX Transportation Old Main Line Subdivision | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T4297265 — 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: CSX Old Main Line Subdivision Context triple: [Point of Rocks station, railwayLineJunction, CSX Old Main Line Subdivision]
-
A.
CSX RF&P Subdivision
The CSX RF&P Subdivision is a major CSX Transportation rail line in Virginia that forms part of the busy freight and passenger corridor linking Washington, D.C. with Richmond and points south.
-
B.
CSX Capital Subdivision
CSX Capital Subdivision is a CSX Transportation rail line in Maryland that serves as a key freight and commuter corridor between Washington, D.C., and Baltimore.
-
C.
CSX Bellwood Subdivision
The CSX Bellwood Subdivision is a freight rail line in Virginia operated by CSX Transportation, forming part of the company’s network around the Richmond area.
-
D.
CSX Transportation Cumberland Subdivision
CSX Transportation's Cumberland Subdivision is a major freight rail line running through Maryland and West Virginia that also hosts MARC commuter rail service on the Brunswick Line.
-
E.
CSX Trenton Subdivision
The CSX Trenton Subdivision is a freight rail line in the northeastern United States operated by CSX Transportation, forming part of a major corridor between Philadelphia and North Jersey.
- 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: CSX Old Main Line Subdivision Target entity description: The CSX Old Main Line Subdivision is a historic freight rail line in Maryland that traces much of the original route of the Baltimore and Ohio Railroad, one of the oldest railroads in the United States.
-
A.
CSX RF&P Subdivision
The CSX RF&P Subdivision is a major CSX Transportation rail line in Virginia that forms part of the busy freight and passenger corridor linking Washington, D.C. with Richmond and points south.
-
B.
CSX Capital Subdivision
CSX Capital Subdivision is a CSX Transportation rail line in Maryland that serves as a key freight and commuter corridor between Washington, D.C., and Baltimore.
-
C.
CSX Bellwood Subdivision
The CSX Bellwood Subdivision is a freight rail line in Virginia operated by CSX Transportation, forming part of the company’s network around the Richmond area.
-
D.
CSX Transportation Cumberland Subdivision
CSX Transportation's Cumberland Subdivision is a major freight rail line running through Maryland and West Virginia that also hosts MARC commuter rail service on the Brunswick Line.
-
E.
CSX Trenton Subdivision
The CSX Trenton Subdivision is a freight rail line in the northeastern United States operated by CSX Transportation, forming part of a major corridor between Philadelphia and North Jersey.
- F. None of above. chosen
Statements (29)
| Predicate | Object |
|---|---|
| instanceOf |
freight rail line
ⓘ
railway line ⓘ |
| connectsTo | other CSX subdivisions in Maryland ⓘ |
| country |
United States
ⓘ
linked to:
United States of America
|
| electrification | not electrified ⓘ |
| followsRouteOf | Baltimore and Ohio Railroad ⓘ |
| hasLineDesignation |
Old Main Line Subdivision
ⓘ
linked to:
CSX Old Main Line Subdivision
|
| hasPredecessor |
Baltimore and Ohio Railroad Old Main Line
ⓘ
linked to:
Baltimore and Ohio Railroad
|
| heritage | historic railroad line ⓘ |
| historicalOperator |
Baltimore and Ohio Railroad
ⓘ
Chessie System ⓘ |
| historicalSignificance | traces original route of one of the oldest railroads in the United States ⓘ |
| locatedIn |
Maryland
ⓘ
Mid-Atlantic region of the United States ⓘ
linked to:
Mid-Atlantic states
|
| maintainedBy | CSX Transportation ⓘ |
| notableFor | being among the oldest continuously used railroad alignments in the United States ⓘ |
| operator | CSX Transportation ⓘ |
| owner | CSX Transportation ⓘ |
| partOf |
CSX network
ⓘ
linked to:
CSX Transportation
former Baltimore and Ohio Railroad system ⓘ |
| primaryUse | freight transportation ⓘ |
| railGauge | standard gauge ⓘ |
| railwayType | heavy rail ⓘ |
| regionServed |
central Maryland
ⓘ
linked to:
Central Maryland
|
| successorTo | Baltimore and Ohio Railroad main line in Maryland ⓘ |
| trackConfiguration | primarily single track ⓘ |
| trafficType | freight only ⓘ |
| usedFor |
interchange freight traffic
ⓘ
local freight service ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: CSX Old Main Line Subdivision Description of subject: The CSX Old Main Line Subdivision is a historic freight rail line in Maryland that traces much of the original route of the Baltimore and Ohio Railroad, one of the oldest railroads in the United States.
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.
CSX Transportation Metropolitan Subdivision
→
connectsTo
→
CSX Transportation Old Main Line Subdivision
ⓘ
linked to: CSX Old Main Line Subdivision
linked to: CSX Old Main Line Subdivision
linked to: CSX Old Main Line Subdivision