Obligatory only for those who can afford it financially as well as physically, Hajj pilgrimage in Makkah, Saudi Arabia is the fifth and final pillar of Islam which is liable to be performed at least once in a lifetime and occurs annually in the Islamic month of Dhul Hijjah. A huge event in terms of mass gathering, the pilgrimage sees Muslims dressed in simple white clothes, performing their rituals for 10 days.Also Read - 'Say No to Bloodshed': Muslim Man Observes 72-Hour Fast to Protest Against Animal Sacrifice on Eid

History
As per Islamic texts, the tradition of performing Hajj goes back to Prophet Abraham’s (PBUH) time when, on the order of God, he left his wife Hajara and his son Ishmael alone in the desert of Mecca. On one ocassion, Hajara ran to and fro in search of water between the two hills of Safa and Marwah seven times and upon not succeeding, returned to her son only to find him scratching the ground with his leg and a water fountain springing forth from the place. The was the place where God commanded Prophet Abraham (PBUH) to build the Kaaba and to invite people to perform pilgrimage there. The Prophet did as instructed with the help of Ishmael. The Quran mentions that the archangel, Gabriel, brought the Black Stone from Heaven to be attached to the Kaaba. Also Read - Bangladeshi Cleric Issues Fatwa Against Facebook’s ‘Haha’ Emoji, Calls it ‘Totally Haram’ For Muslims

A few years down the line, during the time of “jahiliyyah” in pre-Islamic Arabia, pagan idols were placed around the Kaaba. In 630 CE, another messiah, Prophet Muhammad (PBUH), the last one considered in Islam, led the believers from Medina to Mecca and cleansed the Kaaba by destroying all the pagan idols. Having done so, he then reconsecrated the building to Allah and in 632 CE, performed his first and last pilgrimage there. It was then that Hajj became one of the five pillars of Islam after the Prophet instructed his followers on the rites of it. Also Read - ATS Nabs 2 Clerics From Delhi's Jamia Nagar For Converting Over 1,000 People to Islam in UP

Date
Unlike the Gregorian calendar followed by the West, the Islamic calendar is lunar that is, based on the moon. The starting day of Hajj is the eighth day of the lunar month of Dhul-Hijjah, which changes on the Gregorian calendar every year and ends on the 12th day of Dhul Hijjah.

This year, Hajj will begin from August 9 and Eid-al-Adha will be celebrated in Saudi Arabia on August 11.

Significance
Rooting back to the time of Prophet Abraham (PBUH), the pilgrimage is held following the instructions laid down by Prophet Muhammad (PBUH) which are the re-enactments of the sacrifices and obedience of Prophet Abraham to God almighty. The importance of this event is to seek the blessings of surmountable spiritual rewards and erasing of all previous sins if the Hajj is performed successfully. Hajj gathers millions of Muslims across the world in a spirit of unity and brotherhood.

The annual Hajj pilgrimage in Saudi Arabia enters its climax when Muslims gather at Mount Arafat to offer day-long prayer and recitations from the Quran. The pilgrims gather at Mount Arafat, around 15 km from Mecca for one long day and live in tents from dawn to dusk. Mount Arafat has a great significance in Islam because according to the texts, Prophet Mohammed gave his last sermon at the location.