Millions of Muslims have gathered in Mecca, marking the beginning of the five-day Hajj pilgrimage—the world's largest annual religious gathering. It is year 1446 in the Islamic calendar. Pilgrims are expected to retrace the steps of the Prophet Muhammad,

Saudi Arabia's General Authority for Statistics has announced that the total number of Hajj pilgrims for the year 1446 AH reached 1,673,230.Of this grand total, 1,506,576 pilgrims arrived from outside the Kingdom,

Here is a look at the hajj, one of the largest mass gatherings in the world, which starts in Saudi Arabia on Wednesday.