Metro Line 1 (Millennium Underground)
E71061
Metro Line 1, also known as the Millennium Underground, is Budapest’s historic metro line and one of the oldest electrified underground railway lines in continental Europe, renowned for its heritage status and distinctive yellow trains.
All labels observed (6)
How this entity was disambiguated
This entity first appeared as the object of triple T559048 — 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: Metro Line 1 (Millennium Underground) Context triple: [Budapest, contains, Metro Line 1 (Millennium Underground)]
-
A.
S1 Line
The S1 Line is a medium-capacity maglev rapid transit line in the Beijing Subway system serving the western suburbs of the city.
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B.
Metropolitan line
The Metropolitan line is one of the oldest lines of the London Underground, running from central London into the northwestern suburbs and beyond.
-
C.
Metro Line 3
Metro Line 3 is a major Mexico City Metro route that runs north–south across the city, connecting key residential and commercial areas including the Gustavo A. Madero borough.
-
D.
Northern line
The Northern line is a major London Underground route running north–south across the city, serving key central and suburban areas.
-
E.
Metro A Line
The Metro A Line is a light rail line in Los Angeles County that runs between downtown Los Angeles and Long Beach as part of the region’s Metro Rail system.
- 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: Metro Line 1 (Millennium Underground) Target entity description: Metro Line 1, also known as the Millennium Underground, is Budapest’s historic metro line and one of the oldest electrified underground railway lines in continental Europe, renowned for its heritage status and distinctive yellow trains.
-
A.
S1 Line
The S1 Line is a medium-capacity maglev rapid transit line in the Beijing Subway system serving the western suburbs of the city.
-
B.
Metropolitan line
The Metropolitan line is one of the oldest lines of the London Underground, running from central London into the northwestern suburbs and beyond.
-
C.
Metro Line 3
Metro Line 3 is a major Mexico City Metro route that runs north–south across the city, connecting key residential and commercial areas including the Gustavo A. Madero borough.
-
D.
Northern line
The Northern line is a major London Underground route running north–south across the city, serving key central and suburban areas.
-
E.
Metro A Line
The Metro A Line is a light rail line in Los Angeles County that runs between downtown Los Angeles and Long Beach as part of the region’s Metro Rail system.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
metro line
ⓘ
public transport infrastructure ⓘ underground railway line ⓘ |
| alsoKnownAs |
M1
ⓘ
Millennium Underground ⓘ Yellow Line ⓘ |
| character |
cut-and-cover construction
ⓘ
underground ⓘ |
| colorOnSystemMaps | yellow ⓘ |
| constructionMethod | cut-and-cover ⓘ |
| country | Hungary ⓘ |
| electrification | electric railway ⓘ |
| electrified | yes ⓘ |
| fareSystem | integrated with Budapest public transport network ⓘ |
| hasStation |
Bajcsy-Zsilinszky út station
ⓘ
Hősök tere station ⓘ
linked to:
Hősök tere, Budapest
Mexikói út station ⓘ Oktogon station ⓘ Opera station ⓘ Vörösmarty tér station ⓘ |
| heritageStatus |
World Heritage Site component
ⓘ
historic metro line ⓘ |
| historicDesignation | protected historic monument ⓘ |
| inception | 1896 ⓘ |
| isOneOf | oldest electrified underground railway lines in continental Europe ⓘ |
| locatedIn | Budapest ⓘ |
| notableFeature | distinctive yellow trains ⓘ |
| notableFor |
shallow tunnel depth
ⓘ
short, closely spaced stations ⓘ |
| numberOfTracks | 2 ⓘ |
| openingDate | 1896-05-02 ⓘ |
| operator |
BKV Zrt.
ⓘ
linked to:
Budapesti Közlekedési Vállalat
|
| originalPurpose | to serve the 1896 Hungarian Millennium celebrations ⓘ |
| partOf | Budapest Metro ⓘ |
| regionServed | Central Budapest ⓘ |
| rollingStockColor | yellow ⓘ |
| runsUnder | Andrássy Avenue ⓘ |
| serves |
Andrássy Avenue corridor
ⓘ
linked to:
Andrássy Avenue
Budapest city centre ⓘ
linked to:
Budapest
|
| significance |
first metro line in Budapest
ⓘ
one of the earliest metro lines in Europe ⓘ |
| system | Budapest Metro ⓘ |
| terminus |
Mexikói út
ⓘ
Vörösmarty tér ⓘ
linked to:
Vörösmarty Square
|
| trackGauge | standard gauge ⓘ |
| transportMode | rapid transit ⓘ |
| worldHeritageSiteOf | Budapest, including the Banks of the Danube, the Buda Castle Quarter and Andrássy Avenue ⓘ |
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: Metro Line 1 (Millennium Underground) Description of subject: Metro Line 1, also known as the Millennium Underground, is Budapest’s historic metro line and one of the oldest electrified underground railway lines in continental Europe, renowned for its heritage status and distinctive yellow trains.
Referenced by (14)
Full triples — surface form annotated when it differs from this entity's canonical label.
Banks of the Danube, Buda Castle Quarter and Andrássy Avenue
→
contains
→
Millennium Underground Railway
ⓘ
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)
linked to: Metro Line 1 (Millennium Underground)