ARAFAT, Saudi Arabia (Reuters) - Muslim pilgrims poured onto the plain of Arafat east of Mecca on Tuesday as the sun rose over the rocky hills for the day marking the climax of the annual haj pilgrimage.
They came on foot, by bus and in pick-up trucks from Mina and other sites in the direction of Mecca, adding to a throng which will reach more than two million in the afternoon.
Saudi authorities say more than 1.6 million people have entered Saudi Arabia for the event, the largest religious gathering in the world, which poses a huge logistical and security challenge for the Saudi authorities.
The haj has been marred in previous years by fires, hotel collapses, police clashes with protestors trying to politicize the haj and deadly stampedes caused by overcrowding.
The government is also wary of any militant actions. Al Qaeda-linked militants launched a campaign to destabilize the U.S.-allied monarchy in 2003, and Saudi radicals opposed to the royal family seized control of Mecca's Grand Mosque in 1979.
A representative of Iran's Supreme Leader Ayatollah Ali Khamenei managed to give a speech to a group of Iranian pilgrims at Arafat on Tuesday denouncing "enemies of the Muslim nation."
Shown on Iranian TV, pilgrims waved signs saying "Death to America" and "Death to Israel" and chanted slogans. President Mahmoud Ahmadinejad is performing haj this year at the invitation of Saudi Arabia, a close U.S. ally.
Some of the most enthusiastic pilgrims spent the night on Mount Arafat, also known as Jabal al-Rahma or the Mountain of Mercy, nestling in cracks between the boulders. The night air was pleasantly cool, with a breeze from the desert.
Pilgrims perched on the hillside said they had prayed for the welfare and success of Muslims across the world.
Zaki Ali Ibrahim, an Egyptian driver working in Saudi Arabia, said he spent the whole night in prayer with friends.
"I prayed that all Muslims may prosper, and that I may prosper with them," he said. "I felt that my prayers for Muslims were reaching God with strength."
Shazli Atallah Mohamed, a plumber from the southern Egyptian province of Qena, said that on the hilltop he felt he was closer to God than anywhere else on earth. "I prayed that God might accept us all into paradise," he said.
A large group chanted prayers in unison, asking God to help fellow Muslims in areas of conflict including the Palestinian territories, Chechnya, Kashmir and Sudan.
As day spread across the plain, the size of the pilgrimage came to light.
A sea of people wrapped in white cloth streamed along six-lane roads to fill the plain, carrying mats, food, screens against the sun, Korans and prayer books.
Fruit sellers set up stalls and tea stands suddenly appeared. African trader women spread their wares on the ground, offering prayer beads, incense and prayer mats.
One man offered rides in the howdahs of camels, richly decorated with brocade and colored pompoms.
The afternoon at Arafat, known in Arabic as the wuqouf or "standing," is an essential part of the pilgrimage but the requirements are not strict.
The noon prayer and sermon at the Namera Mosque is a major event, evoking the sermon which the Prophet Mohammad made from the hill in the year of his death in 632.