Add to ORKGNorthwest minaret showing bastion encasing the bottom; The Fatimid caliph al-'Aziz (reigned 975-996) began construction in 989 or 990 of a huge mosque (120 x 113 m) just outside the north wall of al-Qahira; his son al-Hakim (reigned 996-1021) completed the building in 1013. It was erected to accommodate not only the ever-burgeoning population of Cairo but also Fatimid pageantry, for the imams visited successive mosques on religious festival days, accompanied by much cermonial pomp. The bastions erected in 1010-1011 to encase the minarets are the most enigmatic feature of the mosque. Bloom suggested that the shape of the minarets (square bases leading to polygonal or circular shafts) deliberately alluded to that of those on the Haram in Mecc...