The Kairaouine Mosque is the holiest and second largest in Morocco. Also called Al-Qarawiyyin, it was commissioned by Fatima al-Fihri in 857. Two years later, she founded a madrasa (school) named Al Quaraouiyine. It is now considered to be the world’s oldest university. In the mosque courtyard (called a sahn) is a water basin for wudu, the ritual purification of the body and partial ablution. The arched wall in the background is a mihrab. It points towards the Kaaba in Mecca and is faced during prayer. Behind the cedar wood screen is the main prayer hall. Non-Muslims are prohibited from entering this area.