d to between 150,000 and 300,000. The city's status was further diminished after Vasco da Gama discovered a sea route around the Cape of Good Hope, thereby allowing spice traders to avoid Cairo.
Cairo's political influence diminished significantly after the Ottomans supplanted Mamluk power over Egypt in 1517. Ruling from Constantinople, Sultan Selim I relegated Egypt to a mere province, with Cairo as its capital. For this reason, the history of Cairo during Ottoman times is often described as inconsequential, especially in comparison to other time periods. However, during the 16th and 17th centuries, Cairo remained an important economic and cultural centre. Although no longer on the spice route, the city facilitated the transportation of Yemeni coffee and Indian textiles, primarily to Anatolia, North Africa, and the Balkans. Cairene merchants were instrumental in bringing goods to the barren Hejaz, especially during the annual hajj to Mecca. It was during this same period that al-Azhar University reached the predominance among Islamic schools that it continues to hold today; pilgrims on their way to hajj often attested to the superiority of the institution, which had become associated with Egypt's body of Islamic scholars. By the 16th century, Cairo also had high-rise apartment buildings where the two lower floors were for commercial and storage purposes and the multiple stories above them were rented out to tenants.
Under the Ottomans, Cairo expanded south and west from its nucleus around the Citadel. The city was the second-largest in the empire, behind only Constantinople, and, although migration was not the primary source of Cairo's growth, twenty percent of its population at the end of the 18th century consisted of religious minorities and foreigners from around the Mediterranean. Still, when Napoleon arrived in Cairo in 1798, the city's population was less than 300,000, forty percent lower than it was at the height of Mamluk—and
