The religious center of the Holy City of Makkah is the Haram Mosque and the well of Zamzam.
The present Haram, meaning "sanctuary", dates from 1570 (978 AH), and takes the form of a central quadrangle surrounded by stone walls. Around the inner sanctuary is a marble pavement, the El Mataf. The holiest shrine of Islam, the Ka'aba, is situated at the heart of the Holy Mosque's central courtyard.
The Haram Mosque has a long and glorious tradition of expansion, dating back to 638 (7 AH) when the ever increasing number of Muslims led the second caliph, Umar ibn al-Khattab, to develop the site.
When the late King Abdul Aziz established the modern Saudi state, one of his primary concerns, like that of the early caliphs, was his role in overseeing the well-being of the pilgrims undertaking the annual Hajj. Aware that the Holy Mosque could not support the growing numbers of worshippers, he initiated a refurbishment and expansion program.