The Islamic pilgrimage, or hajj, climaxed Sunday with more than 2 million pilgrims spending the day at Mount Arafat outside Islam's holiest city of Mecca, an emotional ritual that retraces the last journey of Islam's seventh-century Prophet Muhammad.
In Muzdalifah, the pilgrims were performing sunset and night prayers and collecting pebbles for the next phase of the hajj, the ritualistic stoning of the devil. After Monday's dawn prayers, they would head for Mina to cast their stones at three pillars representing the devil.
After the stoning, pilgrims may perform the ritual of sacrifice--slaughtering a camel, sheep or cow to mark the beginning of Eid al-Adha, one of Islam's most important holidays.
At Mount Arafat earlier in the day, helicopters hovered overhead to ensure security and safety, police directed chaotic traffic, volunteers handed out free water from refrigerated trucks to cool off pilgrims in the desert heat and vendors sold cold drinks and snacks.
The hajj chant of "Here I am, oh Almighty, here I am," sounded across Mount Arafat, a gentle hill 12 miles southwest of Mecca. A seemingly endless sea of pilgrims converged on Arafat, where Muhammad delivered his last sermon and bade farewell to his nation in March 632. He died three months later.
At midday, 250,000 pilgrims crowded Namira Mosque to hear a sermon from Saudi Arabia's top religious cleric, Sheik Abdul-Aziz bin Abdullah Al al-Sheik. He said Jerusalem was in the hands of "Jews who are bullying our Muslim brothers in Palestine under the eyes of those protecting human rights."
The pilgrimage is required once in a lifetime of every able-bodied Muslim who can afford it. Saudi Arabia has said that this year close to 2.5 million people were expected to take part in the hajj. Islam has 1.2 billion followers worldwide.
The Day of Arafat is believed to symbolize the day of judgment, when Islam says the dead will rise and every person will stand before God to answer for his deeds. Muslims believe that the last passage of the Quran, Islam's holy book, was revealed to Muhammad during his sermon at Arafat.
The three-mile trip from Mount Arafat to Muzdalifah is called the nafrah, or rush. As the suns sets, pilgrims start leaving the holy mount to Muzdalifah to pray at a monument called al-Mashaar al-Haram and collect the pebbles.
On Tuesday and Wednesday, pilgrims again will perform the stoning of the devil at Mina, then will head to Mecca to circle the Kaaba, a large cubic stone structure covered with a black cloth that is Islam's most sacred site, seven times. Muslims worldwide face the Kaaba during daily prayers.
In 1998, more than 100 pilgrims were trampled to death in a stampede set off during the stoning ritual. Due to the sheer size of the crowds, the hajj frequently has been marred by tragedies. But the two past years have been trouble-free.