Cordoba Mosque, Spain. The mihrab and the dome above the private praying place of the caliph, in the expansion built by Al-Hakam II in 975 AD. The golden mosaic surrounding the horseshoe arch and the dome was made by artists sent from Constantinople by emperor Nicephorus II Phocas… [1280×596] [OC]

…The mihrab is the central niche on the wall of a mosque which marks the direction of Mecca, the direction of prayer, which is called the Qibla. In the case of the Mosque of Córdoba the mihrab was turned into a separate space with a deeply ornate entrance. The Mihrab does not actually face Mecca, as it follows the tradition of the mosques of Damascus, where Abd-al-Rahman I, the constructor of the mosque, prayed during his childhood.

The space in front of the Mihrab in this mosque encloses the maqsurah, the private praying space of the caliph. From here, prayer was conducted, either by the imam or the caliph. The maqsurah, normally to the side of the mihrab, provided a secure space for the caliph and his closest associates and family. The moment of prayer, when the faithful must prostrate themselves, was an opportune moment for betrayal and attack. Although it never occurred in the Mosque of Córdoba, many attacks on rulers took place during this vulnerable moment.

Although the name of a single “architect” as a modern author is not preserved, historical sources indicate that Al-Hakam II himself directed the architectural program with the help of artisans from Cordoba and masters from Byzantium. Al-Hakam asked the Eastern Roman Emperor Nicephorus II Phocas to send a master mosaicist (a mosaic specialist) to decorate the dome of the mihrab, along with materials and gilded tesserae. This dome, with its octagonal base, is part of the most refined ensemble of Al Andalusian caliphal art. It is composed of interlaced ribs, forming an elaborate framework that allows light to enter through a crown of windows with lobed arches. The surfaces are covered with gilded Byzantine mosaics that give the dome its characteristic shine.

As usual, my apologies for inaccuracies and mistakes.