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,

Here is a look at the hajj, one of the largest mass gatherings in the world, which starts in Saudi Arabia on Wednesday. * The hajj is an annual pilgrimage that millions of Muslims make to Mecca with the intention of performing religious rites as taught by the Prophet Mohammad to his followers 14 centuries ago.

In Islam, Muslims are obligated to complete Hajj at least once in their lifetimes if they are able to. See the faithful on their 2025 pilgrimage.