The Mihrab

Mihrab is a semicircular niche in the wall of a mosque that indicates the qibla; that is, the direction of the Kaaba in Mecca and hence the direction that Muslims should face when praying. The wall in which a mihrab appears is thus the "qibla wall."
The Mosque (Mezquita) in Córdoba, Andalucia, Spain. Also called the Great Mosque of Córdoba, it is a former Islamic mosque, and since 1236 a Catholic Christian cathedral.