North Side Main Line (CTA Red Line)
E943372
The North Side Main Line is a major elevated rapid transit corridor in Chicago that carries the Chicago Transit Authority's Red Line trains through the city's North Side neighborhoods.
All labels observed (2)
| Label | Occurrences |
|---|---|
| North Side Main Line (CTA Red Line) canonical | 1 |
| North Side Main Line of the Brown Line | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T11715347 — 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: North Side Main Line (CTA Red Line) Context triple: [Berwyn station (Chicago "L"), isOnCorridor, North Side Main Line (CTA Red Line)]
-
A.
Green Line (CTA) main line
The Green Line (CTA) main line is a principal rapid transit route in Chicago’s 'L' system, running primarily along the South and West Sides and serving as a core corridor that branches to multiple termini.
-
B.
Purple Line (CTA)
The Purple Line (CTA) is a rapid transit route in Chicago primarily serving the northern suburbs and Evanston, with express service to downtown during weekday rush hours.
-
C.
Yellow Line (CTA)
The Yellow Line (CTA), also known as the Skokie Swift, is a short Chicago Transit Authority rapid transit route that runs between Howard and Skokie without serving downtown Chicago.
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D.
Red Line northwest branch
The Red Line northwest branch is a planned rapid transit extension serving the northwestern suburbs as part of the Red Line’s expanded corridor.
-
E.
Orange Line (CTA)
The Orange Line (CTA) is a rapid transit route in Chicago that connects the Loop with Midway International Airport and several Southwest Side neighborhoods.
- 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: North Side Main Line (CTA Red Line) Target entity description: The North Side Main Line is a major elevated rapid transit corridor in Chicago that carries the Chicago Transit Authority's Red Line trains through the city's North Side neighborhoods.
-
A.
Green Line (CTA) main line
The Green Line (CTA) main line is a principal rapid transit route in Chicago’s 'L' system, running primarily along the South and West Sides and serving as a core corridor that branches to multiple termini.
-
B.
Purple Line (CTA)
The Purple Line (CTA) is a rapid transit route in Chicago primarily serving the northern suburbs and Evanston, with express service to downtown during weekday rush hours.
-
C.
Yellow Line (CTA)
The Yellow Line (CTA), also known as the Skokie Swift, is a short Chicago Transit Authority rapid transit route that runs between Howard and Skokie without serving downtown Chicago.
-
D.
Red Line northwest branch
The Red Line northwest branch is a planned rapid transit extension serving the northwestern suburbs as part of the Red Line’s expanded corridor.
-
E.
Orange Line (CTA)
The Orange Line (CTA) is a rapid transit route in Chicago that connects the Loop with Midway International Airport and several Southwest Side neighborhoods.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
elevated railway
ⓘ
rapid transit line segment ⓘ |
| connectsToLine |
Brown Line (CTA)
NERFINISHED
ⓘ
Purple Line (CTA) NERFINISHED ⓘ |
| connectsWith |
Howard Branch
NERFINISHED
ⓘ
North Side elevated trackage NERFINISHED ⓘ State Street Subway NERFINISHED ⓘ |
| electrification | third rail ⓘ |
| fareSystem | Ventra ⓘ |
| hasNumberOfTracks | 4 tracks (in core segments) ⓘ |
| hasOwner | Chicago Transit Authority NERFINISHED ⓘ |
| hasService | 24-hour service ⓘ |
| hasStation |
Addison station (CTA Red Line)
NERFINISHED
ⓘ
Argyle station (CTA Red Line) NERFINISHED ⓘ Belmont station (CTA Red Line) NERFINISHED ⓘ Berwyn station (CTA Red Line) NERFINISHED ⓘ Bryn Mawr station (CTA Red Line) NERFINISHED ⓘ Fullerton station (CTA Red Line) NERFINISHED ⓘ Granville station (CTA Red Line) NERFINISHED ⓘ Howard station (CTA) NERFINISHED ⓘ Jarvis station (CTA Red Line) NERFINISHED ⓘ Lawrence station (CTA Red Line) NERFINISHED ⓘ Loyola station (CTA Red Line) NERFINISHED ⓘ Morse station (CTA Red Line) NERFINISHED ⓘ Sheridan station (CTA Red Line) NERFINISHED ⓘ Thorndale station (CTA Red Line) NERFINISHED ⓘ Wilson station (CTA Red Line) NERFINISHED ⓘ |
| hasUpgradeProject | Red and Purple Modernization Project NERFINISHED ⓘ |
| lineColor | red ⓘ |
| locatedIn |
Chicago, Illinois, United States
ⓘ
surface form:
Chicago
Illinois ⓘ United States of America ⓘ
surface form:
United States
|
| openingDate | 1900s ⓘ |
| operator | Chicago Transit Authority ⓘ |
| ownedBy | City of Chicago NERFINISHED ⓘ |
| partOf |
Chicago 'L'
NERFINISHED
ⓘ
Chicago Transit Authority Red Line NERFINISHED ⓘ |
| previousOperator |
Chicago Rapid Transit Company
NERFINISHED
ⓘ
Northwestern Elevated Railroad NERFINISHED ⓘ |
| primaryFunction | carries Red Line trains through Chicago's North Side neighborhoods ⓘ |
| safetySystem | automatic block signaling ⓘ |
| serves | North Side, Chicago NERFINISHED ⓘ |
| structureType | elevated ⓘ |
| trackGauge | standard gauge ⓘ |
| transitType | rapid transit ⓘ |
| undergoingConstruction | track and station reconstruction ⓘ |
| usedBy | Red Line trains NERFINISHED ⓘ |
| usesRollingStock |
CTA 5000-series railcars
NERFINISHED
ⓘ
CTA 7000-series railcars NERFINISHED ⓘ |
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: North Side Main Line (CTA Red Line) Description of subject: The North Side Main Line is a major elevated rapid transit corridor in Chicago that carries the Chicago Transit Authority's Red Line trains through the city's North Side neighborhoods.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
North Side Main Line of the Brown Line