Alexandria of the Byzantine period was a major market and one of the Mediterranean's most busy ports. It continued to have a flourishing shipbuilding industry well into the first century AH (seventh century AD) as the Arabs used it as a point of departure for the fleets headed to invade Byzantine lands.
Travelers and geographers from this time praised the base of Alexandria and its position as a major center for the activities of the Arab naval fleet. They also described its famous lighthouse in detail and their accounts show that it was still standing until the year AH 442 (AD 1050), during the reign of the Fatimid Caliph Al-Mustansir. The lighthouse seemed to no longer be in existence during the reign of the Fatimid Caliph Al-Hakim Bi Amr Allah, because he refused an offer to have it rebuilt.
The traveler Ibn Battuta tells us that during his visit to Egypt in AH 750 (AD 1349), he learned that Sultan Al-Nasir Mohammad Ibn Qala'un had started to build a new lighthouse on the model of the old several years earlier. This means that Sultan al-Nasir may have built a new lighthouse called Burj al-Silsila opposite the site of the old one. The old lighthouse was completely destroyed by the reign of Sultan Al-Ashraf Qaitbay, who built his fort on its foundations .