Hundreds of thousands of Muslim pilgrims began a mass movement out of the holy city of Mecca towards the nearby Mina Valley in Saudi Arabia on Thursday, beginning the hajj.

One of the world's largest annual gatherings and a pillar of the Islamic faith, this year's hajj comes with authorities striving to protect pilgrims from two deadly viruses, Ebola and the MERS coronavirus.

Authorities say close to 1.4 million believers have come from abroad to follow the 1,400-year-old tradition of Prophet Mohammed, alongside pilgrims from Saudi Arabia.

"It is a beautiful feeling," said Aziza Yousfy, 60, from Algeria, before leaving Mecca.

Seeing Mina and Mount Arafat "has always been a dream for me," she said.

Mount Arafat is where the Prophet Mohammed gave his final sermon, after leading his followers on the hajj.

Sayed Tajamul Haq, 64, an Indian pilgrim walking with his wife, voiced hope that "God will accept our prayers for forgiveness and mercy", during an experience he described with a smile as "fantastic."

Pilgrims will move a few kilometres (miles) from Mecca to nearby Mina.

Men wear a seamless two-piece white garment, symbolising a state of purity and emphasising their unity regardless of social status or nationality.

Women also generally wear white, exposing only their faces and hands.

The passage to Mina marks the official start of the hajj on the eighth day of the Muslim calendar month of Dhul Hijja.

In Mina, they will pray and rest before moving on to Mount Arafat for the climax of the pilgrimage rituals on Friday.

*This story was edited by Ahram Online.