Roda Nilometer
E225859
The Roda Nilometer is an ancient structure on Cairo’s Roda Island that was historically used to measure the Nile River’s water level and predict flooding and taxation.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Roda Nilometer canonical | 2 |
| Roda Island Nilometer | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T2016302 — 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: Roda Nilometer Context triple: [Roda Island, hasLandmark, Roda Nilometer]
-
A.
Snake Dike
Snake Dike is a classic, runout slab and dike rock climbing route on the southwest face of Half Dome in Yosemite National Park.
-
B.
Dike
Dike is the Greek goddess of justice and moral order, often depicted as a guardian of human righteousness and fairness.
-
C.
The Dam
The Dam is the official name of the Oregon State Beavers football student section, known for its loud, energetic support at home games in Corvallis.
-
D.
Betania Dam
Betania Dam is a major hydroelectric dam and reservoir in Colombia, known for generating power and supporting irrigation and aquaculture in the Huila region.
-
E.
Kosi Barrage
Kosi Barrage is a major flood-control and irrigation structure built across the Kosi River near the India–Nepal border.
- 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: Roda Nilometer Target entity description: The Roda Nilometer is an ancient structure on Cairo’s Roda Island that was historically used to measure the Nile River’s water level and predict flooding and taxation.
-
A.
Snake Dike
Snake Dike is a classic, runout slab and dike rock climbing route on the southwest face of Half Dome in Yosemite National Park.
-
B.
Dike
Dike is the Greek goddess of justice and moral order, often depicted as a guardian of human righteousness and fairness.
-
C.
The Dam
The Dam is the official name of the Oregon State Beavers football student section, known for its loud, energetic support at home games in Corvallis.
-
D.
Betania Dam
Betania Dam is a major hydroelectric dam and reservoir in Colombia, known for generating power and supporting irrigation and aquaculture in the Huila region.
-
E.
Kosi Barrage
Kosi Barrage is a major flood-control and irrigation structure built across the Kosi River near the India–Nepal border.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
historic monument
ⓘ
hydrological measuring structure ⓘ nilometer ⓘ |
| access | open to visitors ⓘ |
| alsoKnownAs |
Miqyas al-Nil on Roda Island
ⓘ
Nilometer of Rawda Island ⓘ
linked to:
Nilometer
|
| architect | Ahmad ibn Muhammad al-Hasib ⓘ |
| architecturalStyle | Abbasid architecture ⓘ |
| city | Cairo ⓘ |
| commissionedBy |
Abbasid Caliph al-Mutawakkil
ⓘ
linked to:
al-Mutawakkil
|
| continent | Africa ⓘ |
| country | Egypt ⓘ |
| culturalContext |
Abbasid Caliphate
ⓘ
Islamic Egypt ⓘ
linked to:
Islam in Egypt
|
| era | Abbasid period ⓘ |
| function |
calibrating expectations for irrigation
ⓘ
monitoring annual Nile inundation ⓘ |
| governingBody |
Egyptian Ministry of Antiquities
ⓘ
linked to:
Egyptian Ministry of Tourism and Antiquities
|
| hasPart |
central measuring column
ⓘ
inscribed measurement marks ⓘ stone staircase ⓘ vaulted roof ⓘ water well ⓘ |
| height | about 13 meters ⓘ |
| heritageDesignation | historic Islamic-era monument ⓘ |
| inception |
861 CE
ⓘ
9th century ⓘ |
| isPartOf | Roda Island ⓘ |
| locatedIn |
Cairo
ⓘ
Egypt ⓘ Roda Island ⓘ |
| locatedOn |
Nile River
ⓘ
linked to:
Nile
an island in the Nile at Cairo ⓘ |
| material | stone ⓘ |
| measurementScale | Nile cubits ⓘ |
| near |
Fustat
ⓘ
Old Cairo ⓘ
linked to:
Coptic Cairo
|
| significance |
important for understanding historical Nile flood patterns
ⓘ
key monument of early Islamic Cairo ⓘ linked to historical tax assessment in Egypt ⓘ oldest surviving nilometer in Egypt ⓘ |
| status |
preserved monument
ⓘ
tourist attraction ⓘ |
| usedFor |
assessing agricultural prospects
ⓘ
determining taxation levels ⓘ flood forecasting ⓘ measuring Nile water level ⓘ predicting Nile floods ⓘ |
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: Roda Nilometer Description of subject: The Roda Nilometer is an ancient structure on Cairo’s Roda Island that was historically used to measure the Nile River’s water level and predict flooding and taxation.
Referenced by (3)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Roda Nilometer