The mihrab or prayer niche is located within the thickness of the qibla wall. It is framed by a horseshoe arch arch decorated with gold and color tesserae (small colored pieces of glass). The mosaic work was carried out by craftsmen brought from Constantinople at the request of Caliph Al-Hakam II. The mihrab was placed in the central aisle of the original 11-aisle-wide mosque and that relative position was maintained through subsequent renovations that displaced the qibla wall southwards. The fourth and last enlargement added aisles on the east side of the mosque, yet the Mihrab remained in its original placement.