Thacher Island North Tower
E106079
Thacher Island North Tower is a historic lighthouse on Thacher Island off the coast of Massachusetts, serving as one of a rare pair of twin navigational beacons for Atlantic maritime traffic.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Thacher Island North Tower canonical | 3 |
How this entity was disambiguated
This entity first appeared as the object of triple T894534 — 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: Thacher Island North Tower Context triple: [Thacher Island, hasStructure, Thacher Island North Tower]
-
A.
Enger Tower
Enger Tower is a historic stone observation tower in Duluth, Minnesota, offering panoramic views of the city, Lake Superior, and the surrounding landscape.
-
B.
Shell Tower
Shell Tower, now known as A’DAM Tower, is a prominent high-rise landmark in Amsterdam that has been transformed from a former corporate office building into a mixed-use cultural, entertainment, and business hub overlooking the IJ river.
-
C.
Prince Rupert's Tower
Prince Rupert's Tower is a historic 18th-century lock-up in Everton, Liverpool, that has become an iconic symbol associated with Everton Football Club.
-
D.
Bay Wellington Tower
Bay Wellington Tower is a prominent office skyscraper in downtown Toronto that forms part of the Brookfield Place complex.
-
E.
Point Sur Lighthouse
Point Sur Lighthouse is a historic 19th-century light station perched on a volcanic rock along California’s Big Sur coast, guiding ships along the rugged Pacific shoreline.
- 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: Thacher Island North Tower Target entity description: Thacher Island North Tower is a historic lighthouse on Thacher Island off the coast of Massachusetts, serving as one of a rare pair of twin navigational beacons for Atlantic maritime traffic.
-
A.
Enger Tower
Enger Tower is a historic stone observation tower in Duluth, Minnesota, offering panoramic views of the city, Lake Superior, and the surrounding landscape.
-
B.
Shell Tower
Shell Tower, now known as A’DAM Tower, is a prominent high-rise landmark in Amsterdam that has been transformed from a former corporate office building into a mixed-use cultural, entertainment, and business hub overlooking the IJ river.
-
C.
Prince Rupert's Tower
Prince Rupert's Tower is a historic 18th-century lock-up in Everton, Liverpool, that has become an iconic symbol associated with Everton Football Club.
-
D.
Bay Wellington Tower
Bay Wellington Tower is a prominent office skyscraper in downtown Toronto that forms part of the Brookfield Place complex.
-
E.
Point Sur Lighthouse
Point Sur Lighthouse is a historic 19th-century light station perched on a volcanic rock along California’s Big Sur coast, guiding ships along the rugged Pacific shoreline.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
historic structure
ⓘ
lighthouse ⓘ navigational aid ⓘ |
| associatedWith |
Thacher Island
ⓘ
surface form:
Thacher Island Association
Thacher Island South Tower ⓘ |
| category |
Buildings and structures in Rockport, Massachusetts
ⓘ
Lighthouses in Massachusetts ⓘ |
| coast |
Massachusetts coastline
ⓘ
surface form:
Massachusetts coast
|
| constructionMaterial | granite ⓘ |
| country |
United States of America
ⓘ
surface form:
United States
|
| distinction |
one of a rare pair of twin lighthouses
ⓘ
only operating twin lighthouses in the United States ⓘ |
| focalHeight | about 166 feet ⓘ |
| function |
mark approach to Cape Ann
ⓘ
warn ships of offshore hazards ⓘ |
| height |
41 meters
ⓘ
about 124 feet ⓘ |
| heritageDesignation |
National Historic Landmark
ⓘ
National Register of Historic Places ⓘ
surface form:
National Register of Historic Places listing
|
| historicUse | guide transatlantic shipping lanes ⓘ |
| lanternColor | black ⓘ |
| lightCharacteristic | flashing white light ⓘ |
| lightRange | about 19 nautical miles ⓘ |
| locatedIn |
Essex County, Massachusetts
ⓘ
Massachusetts ⓘ Rockport, Massachusetts ⓘ United States of America ⓘ
surface form:
United States
|
| locatedInBodyOfWater | Atlantic Ocean ⓘ |
| locatedNear |
Cape Ann
ⓘ
Rockport Harbor ⓘ |
| locatedOn | Thacher Island ⓘ |
| managedBy |
Thacher Island
ⓘ
surface form:
Thacher Island Association
|
| managedInCooperationWith |
Rockport
ⓘ
surface form:
Town of Rockport
|
| marking | unpainted granite tower ⓘ |
| NRHPType | contributing property ⓘ |
| operator | United States Coast Guard ⓘ |
| originalLensType | first-order Fresnel lens ⓘ |
| ownedBy | United States government ⓘ |
| partOf |
Thacher Island Light Station
ⓘ
Thacher Island National Wildlife Refuge ⓘ Thacher Island Twin Lights ⓘ |
| purpose |
aid to navigation
ⓘ
guide Atlantic maritime traffic ⓘ |
| region | New England ⓘ |
| status | active lighthouse ⓘ |
| towerShape | conical tower ⓘ |
| twinWith | Thacher Island South Tower ⓘ |
| yearBuilt | 1861 ⓘ |
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: Thacher Island North Tower Description of subject: Thacher Island North Tower is a historic lighthouse on Thacher Island off the coast of Massachusetts, serving as one of a rare pair of twin navigational beacons for Atlantic maritime traffic.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.