The Great Mosque at Mecca encloses the Kaaba, and with it the Black Stone, the Maqam Ibrahim, the well of Zamzam and the hills of Safa and Marwa walked during the sai. It is the most sacred site in Islam and the direction to which Muslims everywhere pray. More than five million people perform the hajj each year and far more the lesser pilgrimage of umrah. The mosque is run by the General Presidency for the Affairs of the Two Holy Mosques under the Saudi king.