Breathtaking Photos of One of the World’s Biggest Religious Pilgrimages

— -- Every year, millions of Muslims from all over the world gather in Mecca and Medina, Saudi Arabia, for Hajj, the annual pilgrimage that is one of Islam’s five pillars.

This year, three million people are expected to take part in the five day event that occurs in the twelfth month of the Islamic calendar.

Every individual of the Islamic faith is supposed to do the pilgrimage at least once in their lifetime in order to foster a spiritual bond between followers.

Despite a recent crane crash that killed 100 people and security concerns, men and women partake in Hajj.

A sea of people wearing white garments called Ihram could be seen circling the holy shrine, Kaaba, at the Grand Mosque starting on Tuesday.