Caliph Abd al-Rahman I began construction of the mosque in 785, on the site of a Visigothic church in Córdoba. Four successive enlargements over the following two centuries — especially under al-Hakam II (961-976) — turned the building into the largest single religious structure of the medieval Islamic world.

The essence of the architectural programme is not scale but rhythm. The 856 columns that carry the roof (many of them Roman and Visigothic spolia) support arches whose voussoirs alternate red brick and white stone, producing a striped effect. Above these is built a second tier of arches — a solution borrowed from Umayyad Syria — and so a tall space is achieved on short supports. To the visitor it appears an endless forest of columns; the prayer hall is undefined, open, and disperses the gaze rather than directing it.

The mihrab chamber is the opposite — intensely concentrated. Mosaic artisans brought from Byzantium worked vegetal motifs on a gold ground; the surrounding arches turn into a geometric labyrinth. The contrast — wide, cool, numerical column hall against narrow, warm, luminous mihrab — is a mature statement of Islamic spatial thinking.

In 1236 King Ferdinand III of Castile took Córdoba and the mosque was consecrated as a cathedral. In 1523 a full Renaissance cathedral was built into its very centre — an intervention even Emperor Charles V is said to have regretted. The building was inscribed on the UNESCO World Heritage List in 1984.