Around two million worshippers start Hajj pilgrimage in Saudi Arabia

Some two million Muslim pilgrims have officially begun the annual Hajj pilgrimage, making their way out of Mecca after circling Islam's holiest site, the Kaaba, and converging on a vast tent camp in the nearby desert for a day and night of prayer.

Pilgrims have been doing the ritual circuit around the Kaaba since arriving in Mecca in recent days. As the last ones performed it on Monday, the pilgrims made their way by foot or by bus to Mina, where they will camp in one of the largest tent cities in the world.

They will pray throughout the day and night before travelling on Tuesday to Mount Arafat, where the Prophet Muhammad is said to have delivered his final sermon.

After Arafat, pilgrims collect pebbles from a site known as Muzdalifa to be used in the symbolic stoning of pillars representing the devil back in Mina.

Mina is vast and open, with little respite from the desert heat and blazing sun. Soldiers sprayed pilgrims with water to cool them down.

Islam pillars

The pilgrimage is one of the five pillars of Islam, and all Muslims are required to make the five-day Hajj at least once in their lives if they are physically and financially able to do it.

For pilgrims, it is a deeply moving spiritual experience that absolves sins, brings them closer to God and unites the world's more than 1.8 billion Muslims. Some spend years saving up money and waiting for a permit to embark on the journey.

The rituals during Hajj largely commemorate the Quran's accounts of Ibrahim, his son Ismail and Ismail's mother Hajar.

The final three days of the Hajj coincide with the festive Eid al Adha holiday when Muslims around the world distribute the meat of livestock to the poor.