The expansion of Islam into non-Arab territory also increased the number of adherents, mainly during the rule of the Ottoman Empire. Suleiman the Magnificent ruled from 1520-1564 during which Islam reached its greatest penetration into western Europe, taking Belgrade and Vienna. In the practice of Islam, the mosque is the place of public worship. It must have a minaret from which Muslims are called to prayer and be oriented toward Mecca. Mecca is the holiest site in Islam, being the place where the Ka'ba is located.
Medina is the second holiest site, and Jerusalem is the third.
The site is now marked by the Dome of the Rock and the Mosque of Hadhrat 'Umar. The issue of control over the temple mount is a current source of contention between Islam and Judaism . The Viking Press, 1967. Blackwell Publishers, 1996. English Translation of the Meanings and Commentary .