ge to the mosque. The present heavily corbelled and scalloped towers, which rise out of the heart of the two square salients, belong to the renovation work undertaken after the earthquake by the great Mamluk leader Baybars in 1304. The restoration also extended to a few aisles of the prayer hall which regretfully replaced original damaged pointed arches with horseshoe ones, a feature which destroyed some of the rhythm of these aisles. Many of the remaining parts of the mosque still retain much of their original character; sections of the prayer hall with their piers and arches, for example, as well as the mihrab dome survived almost intact. The walls still retain many of their original features and the entrance and minarets much of their bas-relief floriated Kufic friezes, interlineated upended plaques and decorated string course mouldings.
The mosque courtyard or Sahn is a large open area surrounded by a covered arcade (porticoes), three riwaqs deep except from the north western side which is only two riwaqs wide. The boundary walls around the courtyard and on the exterior are surmounted by battlements, a feature which was first introduced to Egypt in Ibn Tulun Mosque and later re-employed in Al-Azhar. This is another motif that was transmitted to Europe, most probably through the influence of mosques of Ibn Tulun, Al-Azhar and Al-Hakim mosques. An example of this is the architect of Palermo Cathedral, built in 1185 CE, who seems to have been so impressed with these battlements that he employed them in the cathedral.