Jerusalem is the Holy city of Judaism, Christianity and of Islam. The city thrived under the Mamluks, who promoted its status as the prime destination for pilgrims, religious scholars and scientists by initiating grandiose architectural projects. Indeed, Jerusalem became such a popular destination for intellectual exchange, mystic introspection and interfaith debate that the number of generously endowed madrasas and other study centres, staffed by some of the most learned intellectuals of the day, increased to over 100.