Portuguese Cistern: Underground Reservoir of El Jadida
Site at a Glance
- Rating
- 4.2
- Popularity
- Medium
- Country
- Morocco
- Primary era
- Early Modern
- External website
- Open
- Eras represented
- Early Modern
- Civilizations
- Portuguese
- Site type
- Infrastructure
- Remains
- Cistern
On this page8 sections
History
The Portuguese Cistern is a sixteenth-century underground reservoir in El Jadida, Morocco, associated with the Portuguese fortified city of Mazagan and built in the late Gothic Manueline style. It lies beneath the citadel at the heart of the former Portuguese settlement. The citadel was the first permanent Portuguese structure on the site, established in 1514, before the larger fortress was expanded from 1541.
From citadel to fortified city
The chamber’s original purpose remains uncertain. It has been identified as a possible granary, armory, or barracks before being converted into a water reservoir during the major fortification works that began in 1541. The expansion created a fortress with broad walls and a moat, and continued between 1541 and 1548. A dependable water supply was essential because the Portuguese position faced attacks and blockades by Moroccan forces.
The cistern is attributed to Miguel de Arruda, a Portuguese architect, while construction work was assigned to João de Castilho, a Portuguese architect and master builder. The precise method used to supply the reservoir has not been established through excavation. Historical indications point to a well west of the fortress walls, from which water may have travelled through underground channels. Rainwater also contributed to the supply.
Capture, restoration, and changing names
After a prolonged siege, the army of Sultan Sidi Muhammad ibn Abd Allah captured the city in 1769. As the Portuguese departed, they set a trap that caused an explosion after the liberation forces entered, although the walls and buildings largely remained standing. Sultan Moulay Abd al-Rahman ordered restoration and rebuilding in 1832. The settlement later became known as Al-Burayja and El Jadida, was called Mazagan again during the French Protectorate, and returned to the name El Jadida after independence.
Public opening and heritage protection
The cistern opened to the public in May 1918. El Jadida was designated national heritage through royal decrees issued on 3 November 1919 and 15 April 1924. In 2004, the old walled city, including the cistern, became part of a UNESCO World Heritage Site, a designation for places recognized as having outstanding cultural or natural value and receiving international heritage protection.
Remains
The Portuguese Cistern is a semi-subterranean chamber with an approximately square plan, measuring about 34.8 by 33.8 metres. Its roof is formed by interconnected fired-brick vaults in the late Gothic Manueline style associated with Portugal. The vaults rise about 5 metres above the floor, while the roof presents a flat appearance from outside.
Vaults and supporting structure
Twenty-five carved stone pillars and columns support the roof in five rows of five. Twelve of the supports are circular and thirteen are square. Their regular arrangement divides the chamber beneath the continuous vaulted ceiling, while the masonry construction reflects the adaptation of late Gothic Portuguese architecture to a fortified setting.
Water collection and drainage
A single opening at the centre of the roof admits a shaft of light and collects rainwater. A central well shaft, originally positioned above the roof, remains visible inside the chamber. Water also reached the reservoir through underground channels carrying water from springs and rainfall, although the exact supply system has not been identified. An overflow channel in the wall between the Stork and Rampart towers carried excess water outside the cistern.
Floor, capacity, and access
The floor is paved with longitudinal red fired-brick units joined with lead to prevent leakage. It slopes toward the centre of the chamber, which could hold about 5,000 square metres of water. Traces of the maximum water level remain visible on the walls and pillars. Side stairs between the Rampart and Prison towers lead to the roof through a gateway that is currently locked.
A thin layer of water across the floor reflects the light entering through the central opening. These changing reflections are a particularly noted feature of the chamber, produced by the relationship between its water surface, vaulted roof, and controlled shaft of daylight.
