Millions of pilgrims converge on Saudi Arabia for Hajj It's one of the largest religious gatherings in the world: the Hajj pilgrimage is underway this week in Saudi Arabia, with some 2 million Muslims converging in Mecca and at Mount Arafat. This year's Hajj could be the largest on record, according to officials, after several quieter years during the Covid-19 pandemic. We take a closer look.