Fort Mahan
E675634
Fort Mahan was a Union Army earthwork fortification in Washington, D.C., built to help defend the U.S. capital during the American Civil War.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Fort Mahan canonical | 4 |
How this entity was disambiguated
This entity first appeared as the object of triple T7586369 — 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: Fort Mahan Context triple: [Civil War Defenses of Washington, hasPart, Fort Mahan]
-
A.
Fort C. F. Smith
Fort C. F. Smith was a 19th-century U.S. Army post in Montana Territory that protected travelers along the Bozeman Trail and became a focal point of conflict during Red Cloud's War.
-
B.
Camp Richardson
Camp Richardson is a historic lakeside resort and recreation area on the south shore of Lake Tahoe in California, offering lodging, camping, beaches, and outdoor activities.
-
C.
Camp Meade
Camp Meade was the original World War I-era U.S. Army training installation that later became known as Fort Meade in Maryland.
-
D.
Fort McRee
Fort McRee was a 19th-century coastal defense fortification guarding the entrance to Pensacola Bay in Florida as part of the United States’ historic seacoast defense network.
-
E.
Fort Cronkhite
Fort Cronkhite is a former World War II-era coastal defense fortification in Marin County, California, now preserved as part of the Golden Gate National Recreation Area and used for recreation and historic interpretation.
- 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: Fort Mahan Target entity description: Fort Mahan was a Union Army earthwork fortification in Washington, D.C., built to help defend the U.S. capital during the American Civil War.
-
A.
Fort C. F. Smith
Fort C. F. Smith was a 19th-century U.S. Army post in Montana Territory that protected travelers along the Bozeman Trail and became a focal point of conflict during Red Cloud's War.
-
B.
Camp Richardson
Camp Richardson is a historic lakeside resort and recreation area on the south shore of Lake Tahoe in California, offering lodging, camping, beaches, and outdoor activities.
-
C.
Camp Meade
Camp Meade was the original World War I-era U.S. Army training installation that later became known as Fort Meade in Maryland.
-
D.
Fort McRee
Fort McRee was a 19th-century coastal defense fortification guarding the entrance to Pensacola Bay in Florida as part of the United States’ historic seacoast defense network.
-
E.
Fort Cronkhite
Fort Cronkhite is a former World War II-era coastal defense fortification in Marin County, California, now preserved as part of the Golden Gate National Recreation Area and used for recreation and historic interpretation.
- F. None of above. chosen
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
Civil War fortification
ⓘ
Union Army fortification ⓘ earthwork fort ⓘ |
| associatedWith |
Defenses of Washington command
ⓘ
linked to:
Union defenses of Washington, D.C.
Union Army Corps of Engineers ⓘ
linked to:
U.S. Army Corps of Engineers
|
| builtBy |
United States Army Corps of Engineers
ⓘ
linked to:
U.S. Army Corps of Engineers
|
| builtFor |
defense of Washington, D.C.
ⓘ
protection of the U.S. capital ⓘ |
| category |
American Civil War forts in Washington, D.C.
ⓘ
Earthwork fortifications ⓘ Military history of Washington, D.C. ⓘ Union Army forts ⓘ |
| city | Washington, D.C. ⓘ |
| conflict | American Civil War ⓘ |
| constructionMaterial | earthworks ⓘ |
| controlledBy | Union Army ⓘ |
| country |
United States
ⓘ
linked to:
United States of America
|
| currentUse |
historic site
ⓘ
public park area ⓘ |
| era | 19th century ⓘ |
| fortType |
enclosed earthwork
ⓘ
field fortification ⓘ |
| function | to guard approaches to Washington from the northeast ⓘ |
| garrisonedBy | Union troops ⓘ |
| hasRemains | traces of earthworks ⓘ |
| heritageStatus | historic Civil War site ⓘ |
| locatedIn |
Northeast Washington, D.C.
ⓘ
United States capital region ⓘ Washington, D.C. ⓘ |
| locatedOn | a hilltop ⓘ |
| militaryBranch |
Union Army artillery
ⓘ
linked to:
United States Artillery Corps
|
| namedAfter |
Dennis Hart Mahan
ⓘ
Professor D. H. Mahan ⓘ
linked to:
Dennis Hart Mahan
|
| namedAfterAffiliation | United States Military Academy ⓘ |
| namedAfterOccupation | military engineer ⓘ |
| overlooks |
Baltimore Turnpike
ⓘ
linked to:
Baltimore–Annapolis Boulevard
railroad approaches to Washington ⓘ |
| partOf |
Civil War defenses of Washington
ⓘ
linked to:
Civil War Defenses of Washington
Defenses of Washington ⓘ |
| region |
Mid-Atlantic United States
ⓘ
linked to:
Mid-Atlantic states
|
| role |
artillery position
ⓘ
observation point ⓘ |
| significance | part of the ring of forts protecting the national capital ⓘ |
| state | District of Columbia ⓘ |
| theater | Eastern Theater of the American Civil War ⓘ |
| usedBy | Union Army ⓘ |
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: Fort Mahan Description of subject: Fort Mahan was a Union Army earthwork fortification in Washington, D.C., built to help defend the U.S. capital during the American Civil War.
Referenced by (4)
Full triples — surface form annotated when it differs from this entity's canonical label.