More than 2 million Muslims are gathering today on Mount Arafat and the surrounding plains at one of the cornerstones of the hajj pilgrimage in Saudi Arabia.
The Prophet Muhammad is said to have delivered his farewell sermon on the rocky desert hill 14 centuries ago.
Muslims believe that on this day the doors of heaven open to answer prayers and grant forgiveness.
"It is an indescribable feeling," Syrian pilgrim Muhammad Babaki told Reuters at the foot of Mount Arafat. "On this day of forgiveness, we hope that God forgives all and accepts their pilgrimage."
Tens of thousands of white-robed pilgrims began their ascent from the tent city of Mina at dawn, chanting: "Here I am, God, answering your calling.”
Charities and vendors handed out food and umbrellas to protect the pilgrims from the sun.
The hajj began November 14 with pilgrims flowing from the city of Mecca or directly into Mina.
After sunset, the pilgrims will move to Muzdalifa to collect pebbles to stone a set of walls. The ritual represents defiance of the devil and commitment to resisting temptation.
The hajj -- one of the world's biggest displays of mass religious devotion -- lasts for five days.
Islam is now embraced by one-quarter of the world's population and the hajj is a duty for all able-bodied Muslims who can afford it to perform at least once.
Saudi officials say they granted permits to 1.7 million pilgrims from foreign countries, with some 200,000 reserved for pilgrims coming from within Saudi Arabia or neighboring Gulf states. But reports say tens of thousands of unauthorized pilgrims had made their way to the plain of Arafat at night in preparation for today’s solemn ritual.
Saudi authorities have taken new measures to improve crowd management. This year's hajj has been incident-free since the pilgrims began gathering in Mecca.
In recent years, the hajj pilgrimage has been marred by fires, hotel collapses, police clashes with protesters, and deadly stampedes. In 2006, more than 360 people were crushed to death by a stampeding crowd.
A Chinese-built train calling at hajj sites is in operation for the first time in a bid to reduce the risk of overcrowding and to lessen congestion on the roads. It is expected to transport some 180,000 passengers during the five-day event.
Attacks by Al-Qaeda's regional wing have not been ruled out by Saudi authorities this year, prompting the deployment of Saudi combat forces. But Al-Qaeda in the Arabian Peninsula said in a statement it had no intentions of targeting pilgrims during hajj.
compiled from agency reports