The hajj reached its high point Sunday when Muslims from across the world converged on a stony hill in Saudi Arabia, a year after the worst tragedy in the pilgrimage's history.
More than 1.8 million people gathered from sunrise to sunset at the hill and a vast surrounding plain known as Mount Arafat, about 15 kilometres (nine miles) from Mecca.
In stifling heat they chanted a traditional hajj incantation, "God, here I am," spending the most important day of the annual hajj in prayer and reading from the Koran.
After sunset, the throng was on the move aboard buses heading for nearby Muzdalifah, in preparation for the first hajj stoning ritual since a deadly stampede during last year's pilgrimage.
Arafat is the site where Muslims believe the Prophet Mohammed gave his last sermon about 14 centuries ago after leading his followers on the pilgrimage.
"I have the impression of standing exactly in front of God," said Khadem Ndyaye, 47, of Senegal.
"Muslims came here from everywhere and we are all the same. If all the world was like that, there wouldn't be any war. Here, we feel that Islam is a religion of peace."
A teenage Indian pilgrim, who gave her name only as Janifa, said she had travelled with her parents.
"I truly am lucky, and very grateful," she said, draped in white under a green parasol.
Another Indian, Mohammed Arafan, 40, said he felt "chosen by God" for being able to perform the hajj.
"It's beautiful to see the Muslims of the world pray together here."
At midday prayers, hundreds of thousands prostrated themselves, men and women side-by-side, in wide alleys that run between prefabricated pilgrim lodgings.
For the first time in years, Saudi Arabia's Grand Mufti Abdul Aziz al-Sheikh did not give his traditional Arafat sermon.
Okaz newspaper cited health reasons, but Sheikh still attended the sermon given in his place by Abdul Rahman al-Sudais, imam of Mecca's Grand Mosque.
From a distance, the hill appeared a snowy white because of the seamless two-piece white garment, ihram, worn by male pilgrims. Women also usually wear white.
They come from every corner of the globe for the hajj, but Indonesia -- the most populous Muslim nation -- has the largest contingent.
Trucks loaded with bottled water were stationed throughout, and pilgrims doused themselves.
Empty bottles and leftover meals littered the ground as ambulances patrolled.
At Muzdalifah, half way between Arafat and Mina, pilgrims gather 49 pebbles for a symbolic stoning of the devil which begins on Monday, in the last major rite of hajj.
It coincides with Eid al-Adha, the feast of sacrifice marked by Muslims worldwide.
During last year's stoning ritual in Mina a stampede killed roughly 2,300 people who were on their way to the Jamarat Bridge to perform the rite.
Saudi Arabia issued a death toll of 769, but figures compiled from foreign officials in more than 30 countries gave a tally almost three times higher.
Authorities announced an investigation into the tragedy but no results have ever been released, although a number of safety measures have been taken.
Among these is the distribution of bracelets which store pilgrims' personal data. Roads have also been widened in the Jamarat area, newspapers reported.
Pilgrims have told AFP they feel safe and have noticed organisational improvements.
"The Saudis organise everything for us. We are truly at ease here in Arafat," Youssef al-Mehri, 24, of Oman said with a prayer rug slung over his shoulder.
On Sunday, helicopters monitored the crowd flow from the skies, while on the ground, police directed pedestrian movement.
At the sacred hill itself, officers sometimes had to use their bodies to block the flow of pilgrims and avoid bottlenecks.
Despite the safety and security measures which Sunni-dominated Saudi Arabia says it has taken, Shiite Iran has angrily questioned the kingdom's custodianship of Islam's holiest places.
Iran last year reported the largest number of stampede victims, at 464, and its 64,000 pilgrims are excluded for the first time in decades after the regional rivals failed to agree on security and logistics.
Hundreds of thousands of Iranian faithful held an alternative pilgrimage on Saturday in the Iraqi Shiite holy city of Karbala, according to an official at the shrine of Imam Hussein.
Saudi Arabia on Sunday said it had launched a television channel to broadcast the hajj rituals in the Persian language, also known as Farsi, spoken in Iran