The catastrophic crowd crush in Mina, about 5 kilometres from Mecca on Thursday, was deadliest incident to occur during the pilgrimage in 25 years.
The tragedy occurred as crowds converged on Mina, a large valley about 5m from Mecca, for the ‘stoning of the devil’.
It was second deadly incident to overshadow the Hajj season, after a crane collapse at the Grand Mosque killed 107 people and wounded more than 200.
What is Hajj?
Each year, millions of Muslims from around the world travel to Saudi Arabia to take the pilgrimage to the holy city of Mecca.
The Hajj pilgrimage attracts huge crowds; more than 2 million visitors were expected this year.
The increased accessibility of modern travel means more people than ever are able to travel to Mecca. The average number of visitors has risen from around 100,000 people in the late 1920s, to crowds of between 2 and 3 million today.
Pilgrims flock to the ancient city of Mecca for five days during the 12th month of the Islamic lunar year. Those taking part wear white, and perform a series of rituals which symbolise significant events in Islamic history.
Why do people go?
The journey to Mecca is central to Islamic faith. It is considered the duty of every adult Muslim to perform it at least once in their lives, if they can afford it and are physically able.
What is the stoning of the devil?
Muslim pilgrims throw pebbles at pillars during the "Jamarat" ritual. (AFP photo/Mohammed Al-Shaikh)
During the Hajj, pilgrims travel to Mina, a large valley about 5km from Mecca, to throw 49 stones over three days at three pillars called jamarāt.
It represents when Prophet Abraham stoned the devil and rejected his temptations, according to Islamic faith.
Deadly Hajj incidents
The disaster is the worst to befall the pilgrimage since July 1990, when 1426 pilgrims were crushed in an overcrowded pedestrian tunnel leading to holy sites in Mecca.
In 2006, more than 360 pilgrims were killed in a stampede, also in Mina.
And the day before the 2006 Hajj began, an eight-story building collapsed near the Grand Mosque in Mecca, killing 73 people.
In 2004, a crush at Mina killed 244 and injured hundreds more on the final day of the pilgrimage.
In 2001, a stampede at Mina killed 35 people.
What happens next?
A Muslim pilgrim prays at the Hiraa cave, at the top of Noor Mountain on the outskirts of Mecca, Saudi Arabia. (AAP)
Saudi Arabia's King Salman has ordered a safety review for the Hajj pilgimage, in the wake of Thursday's disaster.
The supreme leader of Iran, which lost at least 95 of its citizens in the crush, said the Saudi government's "mismanagement and improper actions" were to blame for the disaster.
However, immediately following the tragedy, the Saudi health minister, Khaled al-Falih, suggested the pilgrims themselves were to blame, because they failed to "follow instructions".
Kind Salman said there was a need "to improve the level of organisation and management of movement" of pilgrims doing the Hajj pilgrimage.
