The name Nun’s Well is a misnomer. There were never any nuns here or at the Shrine. It is however marked as such in several old maps of Gibraltar. One possible explanation for this confusion is the fact that the Shrine, just a few hundred metres to the north, was dedicated to Our Lady of Europe and the British associated the area which venerated the Virgin with Nun’s. George Palao put forward another theory: that the name the cistern at Nun’s Well was a corruption of the cistern at Inan’s Wall in relation to a defensive wall built nearby on the orders of the Marinid Sultan Abu Inan Faris.
The southern plateau known as Europa Flats was later called by the Spaniards ‘Tarfes Bajos’, whilst the Windmill Hill above was known as ‘Tarfes Altos’.2 In any event, the structure represents some of the earliest evidence of an artificial water supply in Gibraltar.
Pedro Barrantes Maldonado mentions the well in his 1540 ‘Dialogue’ claiming that the cistern was Moorish or older:3
‘In the area of the Tarfes and the Corral de Fez, no drinking water can be found, except that of a cistern (aljibe), which in those parts is found, where rainwater is collected, built during the time of the moors or gentiles, with twenty arches and pillars underground, which is very notable and superb; and from this water those who live in those parts take advantage’.
Evidence in support of the view that the structure was older than the Moorish period was provided by the expert opinion of Mr. B. Drissi, Inspector of Antiquities for the Government of Morocco and an expert on Moorish architecture who visited the site on the 18th March 1971. He concluded that it was definitely of an ‘earlier period than the Moorish Dynasties.4 Palao who carried out some further research on the site agreed, and suggested that the structure could have been Visigothic, Roman or even earlier and must have been associated with some kind of settlement or village at some early period of Gibraltar’s past.5
Such is the design and layout of the underground chambers that even its original purpose has often been confused. In the Map of Gibraltar drawn in 1799 by Jean-Denis Barbié du Bocage the location is described as bain des maures [English: The Moorish Baths] but that again is a misnomer as the purpose of the underground structure was to serve as a cistern. The Spanish engineer Cristobal de Rojas also includes the structure in his 1608 map of the Rock referring to it simply as sisternas. Palao suggested that the structure may well have been used for irrigation although he admitted that no exit from the cistern in the form of pipes or channels had yet been found. Curiously, George Palao in his investigation found that there were only twelve brick columns supporting the structure. Yet the oldest map reference available of the Nun’s Well, a sketch by the Dutch Map maker, Anton Van den Wygaerde dated to 1567, seems to show a structure with 20 pillars of which not all support arches, whilst the Spanish historian Ignacio López de Ayala observed that twenty-two pillars support the roof.6 Moreover, Ayala specifically describes the shape of the chamber as being a trapezium [trapezoide] with a length of 78 feet; width of 48 feet and 42 feet respectively; height being 8 ½ feet.
Ayala was full of admiration for the construction claiming that it was of Moorish origin or possibly older: “To the Eastward, and near the Virgen de Europa, was an admirably constructed Cistern or tank for receiving water; so magnificent and of such noble architecture, that it is difficult to divine whether it was the work of the Moors, or of more ancient times.”7
Ayala’s full text in Spanish reads:
Al levante de la virgen de Europa se ofrecía el admirable edificio de la cisterna, aljibe o recogimiento de agua, tal i tan magnífico, i tan grandiosa arquitectura, que no es fácil adivinar si fue obra de moros o más antigua que ellos. Es su forma irregular, de figura trapezoide; larga de setenta i ocho pies; lata 6 ancha cuarenta i ocho, y cuarenta y dos; i la altura es de ocho pies i medio. Para sostener el terrado, que lo cubre tiene veinte i dos pilares de ladrillo, i se baja a él por una escalera del mismo material. Obra, cierto, que fue abierta y levantada por hombres de gran curiosidad; porque está cavada en peña viva, i en todo aquel sitio no se halla otro suelo con espacio tan igual y tan profundo. Tiene labradas las paredes y el pavimento de ladrillo, con fortísima argamasa, cual era menester para retener el agua que se desprende desde las alturas, i se recoge en el depósito. Conservase en éste casi todo el año; pero son muchas las quiebras con que el tiempo lo destruye.8
Drinkwater’s account is almost identical to Ayala’s: “Towards Europa advance is a Moorish bath, called by the garrison, the Nuns well. It is sunk eight feet deep in the rock, is 72 feet long, and 42 feet broad, and, to preserve the water, has an arched roof, supported by pillars.”9