364 The Contribution to Islam made to private collections and to museums, architecture, with its allied art of design and carving, may be studied extensively in situ. The visitor to Egypt to-day, when he has made the tour of the ancient monuments and the museums, will be foolish if he does not capitulate to the importunity of his dragoman to show him the Muslim monuments. The history of the primitive beginnings of Muslim archi- tecture concerns other countries than Egypt—Arabia itself, where the first rude mosque was constructed, Syria, where Christian churches were converted to the worship of Allah, and Iraq, where the Caliphs, using Persian architects, built their own sacred shrines. Nothing was erected worthy of notice in Egypt during the first two centuries of Muslim domination. But the coming of the Tulunids was a signal for the advent of more spacious times. The Ibn Tulun mosque, still extant, was built at the command of Ahmad ibn Tulun, founder of the dynasty: coming from Samarra, he had his building designed on Bagdad lines, decorated after the Samarra fashion. The present minaret was not constructed until 1296. The Fatimid period was an age of great architectural activity. Reference has already been made to the foundation in 972 of the Azhar mosque: though much altered in later times, its original plan may still largely be traced; its transept is the earliest example of this feature in Egypt, though the Great Mosque at Damascus had already incorporated the device. The mosque of al-Hakim, built between 990 and 1012, shows strong Iraqi and Syrian influences. Under Saladin the military defences of Cairo were con- structed, the greater part of the walls, and the Citadel which still overshadows the city. The same ruler introduced the madrasa into Egypt, to house the theological schools: later, a cruciform style was developed, convenient for accommodating professors of the four different persuasions, a plan first evolved in Egypt.