Muslims from across the world are gathering in Makkah in Saudi Arabia for the annual Hajj pilgrimage will take part in the following rituals:
Ihram: For the Muslim faithful, Hajj begins by getting mentally prepared for pilgrimage. Muslims don special clothing, which for men is a two-piece white seamless garment. Women wear loose dress, generally white, with only the face and hands exposed.
Tawaf: Once in Mecca, pilgrims perform Tawaf, by circling seven times counter-clockwise, around the Kaaba in the centre of the Grand Mosque.
Sa'ey: Pilgrims then walk seven times between two stone spots at the mosque, emulating a search for water by the Prophet Abrahim's wife Hagar in a ritual known as Sa'ey. Hagar was seeking water for her infant son Ismail in the hot desert when she found water in the Zamzam well on her seventh try.
These rituals are considered the umrah, or lesser pilgrimage, and come ahead of the Hajj's main rites when pilgrims head to Mina, around five kilometres east of the Grand Mosque.
The next day, pilgrims gather on the hill known as Jebal Al Rahma and the surrounding Mount Arafat plain, 10 kilometres southeast of Mina, where they remain until evening for prayer and to read the Quran.
The Prophet Mohammed delivered his final sermon from Mount Arafat to Muslims who had accompanied him on his final hajj, according to Islam.
Stoning the 'devil'
After sunset, pilgrims leave for Muzdalifah, halfway between Arafat and Mina, where they stay at least until midnight.
They gather pebbles to perform the symbolic "stoning of the devil" on the eve of the Eid Al Adha, which marks the end of Hajj.
At the start of Eid Al Adha, pilgrims return to Mina for the first of three daily stoning rites.
Traditionally, seven pebbles are thrown at a post representing the devil, emulating the actions of Abraham.
Since 2004, the post has been replaced by walls to accommodate the rising numbers of pilgrims.
After the first stoning, sheep are slaughtered and the meat distributed to needy Muslims, symbolising Ibraham's willingness to sacrifice his son Ismail on the order of God, who provided a lamb in the boy's place at the last moment.
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Men then shave their heads or trim their hair while women cut a fingertip-length off their locks. After that they can end their ihram and change back into normal clothing.
Pilgrims return to the Grand Mosque in Mecca, circling seven times around the Kaaba, and again performing Sai.
They then return to Mina to continue the stoning ritual for two or three more days.
Finally, they return to the Grand Mosque, circling the Kaaba seven times.