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Muslim pilgrims circle the Kaaba at the Grand mosque in Mecca during the annual haj pilgrimage November 11, 2010. The haj is one of the world’s biggest displays of mass religious devotion and a duty for Muslims who can perform it (Credit: Reuters/Mohammed Salem)

Muslim pilgrims circle the Kaaba at the Grand mosque in Mecca during the annual haj pilgrimage November 11, 2010. The haj is one of the world's biggest displays of mass religious devotion and a duty for Muslims who can perform it (Credit: Reuters/Mohammed Salem)