As they inch to the climax of a potentially record-breaking Hajj pilgrimage, hundreds of thousands of Muslim pilgrims gathered for the "stoning of the devil" ritual in Saudi Arabia.

From dawn, hundreds of thousands of worshippers began pelting pebbles at three concrete monoliths representing Satan, the last major ritual of an event held in the severe summer heat.

A day after braving temperatures of 48 degrees Celsius (118 degrees Fahrenheit) and praying for hours on Mount Arafat, the pilgrims flocked to Mina, close to Mecca.

As we inch closer to the #Hajj season, here's all you need to know about Hajj and its importance to #Muslims around the world. pic.twitter.com/46tRnC4Fmd

— Al Mayadeen English (@MayadeenEnglish) June 20, 2023

More than 1.8 million pilgrims, most of them from abroad, joined the first Hajj with unrestricted numbers since pre-Covid in 2019, when 2.5 million took part.

The number of attendees, which Saudi officials reported on Tuesday, is well below what they had predicted would surpass the previous record set in 2019.

Flow of worshippers despite sweltering heat

The devil-stoning marks the beginning of the three-day Eid Al-Adha holiday, celebrated by Muslims to commemorate Abraham's willingness to sacrifice his son.

After that, the pilgrims return to Mecca and complete a final "Tawaf" by circumambulating around the Kaaba seven times.

In order to manage the flow of worshippers on Wednesday, helicopters hovered overhead and hundreds of police officers spread out throughout Mina's roads.

The sweltering temperatures have been a significant obstacle for worshippers from 160 different nations, including many elderly people.

In recent years, the Hajj has coincided with the Saudi summer, compounded by global warming that has made the desert climate even hotter.

Tuesday's peak of 48 degrees Celsius made it the hottest day at this year's Hajj. Experts have warned that temperatures of 50 degrees could become an annual occurrence in Saudi Arabia by the end of the century.

Many pilgrims use umbrellas to block the sun as they walk, while others carry folded prayer shawls above their heads to protect themselves from the heat.

According to officials, there are more than 32,000 medical professionals on hand to assist anyone who suffers from heatstroke or other illnesses, and water bottles are being given for free.

The Hajj started on Sunday at Mecca's Grand Mosque, Islam's holiest site, before an overnight stay in tents and then the prayers on Mount Arafat, where Prophet Muhammad gave his final sermon.

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