Two-million Muslim pilgrims head toward the Saudi Arabian tent city of Mina Monday after completing the first leg of their Hajj journey in Mecca.
On Sunday, Muslim pilgrims walked seven times around Mecca's Kaaba -- a large, cube-shaped stone structure in the center of the city's Grand Mosque.
Throughout the world, Muslims turn toward Islam's holiest shrine in Mecca for their daily prayers, recognizing the Kaaba as the house of God, and Mecca as the birthplace of the Prophet Mohammad.
The Hajj pilgrimage now underway includes a walk up nearby Mount Arafat.
Devout Muslims are required to take part in the Hajj at least once during their lifetimes, if they are financially and physically able.
Of one-billion Muslims worldwide, one-and-one-half-million are in Saudi Arabia this year, joining about 500-thousand Saudis also taking part in the Hajj.
Heightened security is in effect for this year's pilgrimage, amid fears of possible military action in neighboring Iraq.