The Islamic architecture of Spain and North Africa: the double-tiered horseshoe arcades of Córdoba, the great Almohad minarets, and the courts, stucco and muqarnas of the Alhambra.
When the Abbasids overthrew the Umayyads in 750, one prince of the old dynasty, Abd al-Rahman, escaped to Spain and founded an independent emirate at Córdoba in 756. The mosque he began in 784–85 grew, through three great extensions over two centuries, into one of the largest buildings of the medieval world, and it defines the western Islamic style. Its builders reused Roman and Visigothic columns and, needing more height than the short shafts allowed, invented the double arcade: piers standing on the columns carry upper round arches, while lower horseshoe arches brace them. The voussoirs alternate red brick and white stone. In the tenth century the caliph al-Hakam II added a new mihrab (a small octagonal room behind a horseshoe arch in an alfiz frame, covered in mosaic made with the help of a Byzantine craftsman) and in front of it bays covered by domes on interlacing ribs.
The horseshoe arch, inherited from Visigothic Spain, became the emblem of the style, together with polylobed and interlaced arches, the rectangular alfiz framing an arch, and surfaces of carved stucco. After the collapse of the caliphate in the eleventh century, the small taifa kingdoms competed in luxury (the Aljafería palace at Zaragoza), and the Berber dynasties from Morocco (the Almoravids and then the Almohads) built severe, grand mosques with great square minarets: the Kutubiyya at Marrakesh, the unfinished Hassan tower at Rabat, and the minaret of Seville, now the Giralda.
The last Islamic kingdom in Spain, the Nasrids of Granada (1238–1492), built the Alhambra. Its architecture is light, even flimsy (rubble and brick walls covered with tile dadoes, carved plaster and painted wood), but its planning is masterly: rooms opening onto long courts of water and myrtle, slender columns, and domes of muqarnas so intricate that they seem made of light. The Hall of the Two Sisters and the Hall of the Abencerrajes, around the Court of the Lions, are the summit of the art of muqarnas in the West.
Moorish architecture outlived Islamic rule. Muslim and later converted craftsmen continued to work for Christian patrons in the Mudéjar style, in the Alcázar of Seville and in countless church ceilings and towers of Aragon; and the style was revived as “Moorish” or “Neo-Mudéjar” in the nineteenth century, from synagogues in Central Europe to railway stations and bullrings.