Updated 1735 GMT (0135 HKT) August 12, 2019
The journey, which is made over five days during the last month of the Islamic calendar, is a chance for Muslims to seek redemption, to forgive and be forgiven. During the pilgrimage a number of detailed rituals are carried out, including wearing special white garments and moving in a counter-clockwise procession around the Kaaba, a cube-shaped structure draped in black silk that is believed to have been constructed by the Prophet Abraham from the Old Testament.
The Prophet Mohammed made the first pilgrimage to Mecca in 628 AD with 1,400 followers. Now, as a way to manage entries, Saudi Arabian authorities require pilgrims to apply via a strict visa application.
Saudi Arabia's Director General of Passports, Maj. Gen. Sulaiman Al Yahya, said that by Wednesday -- two days before the Hajj -- 1.8 million pilgrims had arrived in the country by air, land and sea ports.
In 2018, 2.37 million Muslims made the journey to Mecca -- which is the only Islamic holy site where both men and woman can pray and perform all the Hajj rites together.