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Millions descend on Mecca for Hajj pilgrimage

Fayez Nureldine / AFP - Getty Images

Muslim pilgrims wait for the start of prayers at the Grand Mosque in the Saudi holy city of Mecca on October 22, 2012.

Muslim pilgrims are descending in droves on Mecca for the hajj pilgrimage, which Saudi Arabia insists will not be affected by instability rocking the region. 

Stormy skies greet pilgrims at Mount Noor in Mecca

The annual Islamic pilgrimage, which officially begins on Thursday, October 25, draws three million visitors each year, making it the largest annual gathering of people in the world.

Hajj is among the five pillars of Islam and is required of all able-bodied Muslims at least once in their lifetime.

-- Agence France Presse, The Associated Press

Hassan Ammar / AP

Muslim pilgrims leave the Grand mosque after the noon prayer in Mecca, Saudi Arabia, on Oct. 22, 2012.

Alaa Badarneh / EPA

A view of the Royal Hotel Clock Tower located near the Haram Sharif Mosque during sunset, as seen from the top of the Jabal-al-noor ('Mountain of Light' in Arabic), four days before the Hajj 2012 pilgrimage, near Mecca, Saudi Arabia, on October 21, 2012.

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