A21 motorway (Portugal)
E549153
The A21 motorway in Portugal is a relatively short highway that connects the A8 motorway to the coastal town of Ericeira, serving as an important link between Lisbon’s metropolitan area and the western seafront.
All labels observed (1)
| Label | Occurrences |
|---|---|
| A21 motorway (Portugal) canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T5530627 — 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: A21 motorway (Portugal) Context triple: [Portuguese national road network, hasComponent, A21 motorway (Portugal)]
-
A.
A22 motorway (Portugal)
The A22 motorway, also known as Via do Infante, is a major toll highway running across Portugal’s Algarve region, connecting the Spanish border near Vila Real de Santo António to Lagos.
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B.
A25 motorway (Portugal)
The A25 motorway in Portugal is a major east–west highway linking the coastal city of Aveiro to the Spanish border near Vilar Formoso, serving as a key route for domestic and international traffic across central Portugal.
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C.
A1 motorway (Portugal)
The A1 motorway in Portugal is the country’s main north–south highway, linking Lisbon to Porto and serving as a key backbone of national road transport.
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D.
A28 motorway (Portugal)
The A28 motorway in Portugal is a major coastal highway linking Porto to Viana do Castelo and the northern border region, serving as a key route for traffic along the northwest Atlantic corridor.
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E.
A24 motorway (Portugal)
The A24 motorway in Portugal is a major north–south highway linking Viseu to Chaves and the Spanish border, serving as an important inland route parallel to the coast.
- 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: A21 motorway (Portugal) Target entity description: The A21 motorway in Portugal is a relatively short highway that connects the A8 motorway to the coastal town of Ericeira, serving as an important link between Lisbon’s metropolitan area and the western seafront.
-
A.
A22 motorway (Portugal)
The A22 motorway, also known as Via do Infante, is a major toll highway running across Portugal’s Algarve region, connecting the Spanish border near Vila Real de Santo António to Lagos.
-
B.
A25 motorway (Portugal)
The A25 motorway in Portugal is a major east–west highway linking the coastal city of Aveiro to the Spanish border near Vilar Formoso, serving as a key route for domestic and international traffic across central Portugal.
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C.
A1 motorway (Portugal)
The A1 motorway in Portugal is the country’s main north–south highway, linking Lisbon to Porto and serving as a key backbone of national road transport.
-
D.
A28 motorway (Portugal)
The A28 motorway in Portugal is a major coastal highway linking Porto to Viana do Castelo and the northern border region, serving as a key route for traffic along the northwest Atlantic corridor.
-
E.
A24 motorway (Portugal)
The A24 motorway in Portugal is a major north–south highway linking Viseu to Chaves and the Spanish border, serving as an important inland route parallel to the coast.
- F. None of above. chosen
Statements (31)
| Predicate | Object |
|---|---|
| instanceOf |
motorway
ⓘ
road in Portugal ⓘ |
| connects |
Lisbon metropolitan area
NERFINISHED
ⓘ
western coastal area near Ericeira ⓘ |
| connectsTo | A8 motorway (Portugal) NERFINISHED ⓘ |
| country | Portugal ⓘ |
| directionA | east ⓘ |
| directionB | west ⓘ |
| easternTerminus | A8 motorway (Portugal) NERFINISHED ⓘ |
| hasAccessTo | Ericeira beaches ⓘ |
| hasJunctionWith | A8 motorway (Portugal) NERFINISHED ⓘ |
| hasLaneConfiguration | dual carriageway ⓘ |
| isPartOfCorridor | Lisbon–Ericeira corridor NERFINISHED ⓘ |
| languageOfDesignation | Portuguese ⓘ |
| length | approximately 25 km ⓘ |
| locatedIn |
Lisbon District
NERFINISHED
ⓘ
Mafra Municipality NERFINISHED ⓘ |
| maintainedBy | Brisa – Auto-estradas de Portugal NERFINISHED ⓘ |
| partOf | Portuguese motorway network NERFINISHED ⓘ |
| primaryFunction | link A8 motorway to Ericeira ⓘ |
| regionServed |
Lisbon metropolitan area
NERFINISHED
ⓘ
western seafront of Portugal ⓘ |
| roadNumber | A21 ⓘ |
| roadType | toll motorway ⓘ |
| serves |
Ericeira
NERFINISHED
ⓘ
Mafra Municipality NERFINISHED ⓘ |
| supportsTrafficType | motor vehicle traffic ⓘ |
| terminusNear | Atlantic coast ⓘ |
| usedFor |
commuter traffic to Lisbon area
ⓘ
tourism access to Ericeira ⓘ |
| westernTerminus | Ericeira 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: A21 motorway (Portugal) Description of subject: The A21 motorway in Portugal is a relatively short highway that connects the A8 motorway to the coastal town of Ericeira, serving as an important link between Lisbon’s metropolitan area and the western seafront.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.