Muslim pilgrims are gathering in the Saudi city of Mecca for Islam's annual pilgrimage, which begins Wednesday.
Able Muslims are required to perform the arduous and expensive pilgrimage to Mecca, known as the Hajj, at least once in their lifetime.
Saudi authorities are warning they will stop any disruptive protests over the conflict in Syria.
Saudi Arabia has backed rebels fighting Syrian President Bashar al-Assad, while Iran remains an ally of Syria at a time when relations between Riyadh and Tehran are tense.
Authorities say they are prepared for possible violence during the pilgrimage, which has happened in the past. The most notable case came in 1979, when attackers seized the Grand Mosque. Hundreds of people were killed during a two-week siege.
Muslim pilgrims cast stones at a pillar, symbolizing the stoning of Satan, in a ritual called "Jamarat," a rite of the annual Hajj, the Islamic faith's most holy pilgrimage, in Mina near the Saudi holy city of Mecca, Saudi Arabia, Friday, Oct. 26, 2012.
Youssef, 3, a Muslim pilgrim from Egypt walks with his grandfather to casts stones at a pillar near the Saudi holy city of Mecca, Saudi Arabia, October 26, 2012.
A Muslim pilgrim has his head ritually shaved after he cast stones at a pillar in Mina near the Saudi holy city of Mecca, October 26, 2012.
Muslim pilgrims pray on a rocky hill called the Mountain of Mercy, on the Plain of Arafat near the holy city of Mecca, Saudi Arabia, in the early hours of October 25, 2012.
Muslim pilgrims pray near the holy city of Mecca, Saudi Arabia, October 25, 2012.
Crowds bow in prayer outside the mosque of the Plain of Arafat near Mecca, Saudi Arabia, October 25, 2012.
Muslim pilgrims circle the Kaaba to pray inside the Grand mosque in the holy city of Mecca, Saudi Arabia, October 23, 2012.
A man carries a sheep through a livestock market in Sanaa, October 24, 2012. Muslims around the world celebrate Eid al-Adha to mark the end of the Hajj by slaughtering sheep, goats, cows and camels.
A boy dances with a sheep at a livestock market ahead of Eid al-Adha festival in Sanaa, October 24, 2012.
Muslim pilgrims pray outside the Grand Mosque in the holy city of Mecca, Saudi Arabia, October 23, 2012.
Muslim pilgrims pray outside the Grand Mosque in Mecca, Saudi Arabia, October 23, 2012.
A Muslim pilgrim shops in a gold market in Mecca, October 23, 2012.
Muslim pilgrims leave the Grand mosque after the noon prayer in Mecca, October 22, 2012.
Muslim pilgrims pray outside the Grand mosque in Mecca, Saudi Arabia, October 22, 2012.