Muslim pilgrims pray in front of a pillar, where Islam's Prophet Muhammad is believed to have delivered his last sermon to tens of thousands of followers, on a rocky hill known as Mountain of Mercy, on the Plain of Arafat, during the annual hajj pilgrimage, ahead of sunrise near the holy city of Mecca, Saudi Arabia, Aug 10, 2019. (AMR NABIL / AP)

MOUNT ARAFAT, Saudi Arabia — More than 2 million Muslims are gathered at the sacred hill of Mount Arafat in Saudi Arabia for an intense day of worship and reflection on what's considered the climax of the Islamic hajj pilgrimage.

One of the largest religious gatherings on earth, the second day of the hajj is often the most memorable for pilgrims

Some had tears streaming down their faces as the men, wearing simple white garments, and women raised their hands in worship on the slopes of the rocky hill. Many walked through the pre-dawn darkness early Saturday to the hill where the Prophet Muhammad delivered his final sermon some 1,400 years ago, calling for equality and unity among Muslims.

One of the largest religious gatherings on earth, the second day of the hajj is often the most memorable for pilgrims. They stand shoulder to shoulder with Muslims from around the world seeking God's mercy and blessings.

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Muslim pilgrims pray on a rocky hill known as Mountain of Mercy, on the Plain of Arafat, during the annual hajj pilgrimage, near the holy city of Mecca, Saudi Arabia, Aug 10, 2019. (AMR NABIL / AP)

Pigeons fly as Muslim pilgrims pray on a rocky hill known as Mountain of Mercy, on the Plain of Arafat, during the annual hajj pilgrimage, near the holy city of Mecca, Saudi Arabia, Aug 10, 2019. (AMR NABIL / AP)

Pilgrims walk outside Namira Mosque in Arafat, in Mecca, Saudi Arabia, Aug 9, 2019. (AMR NABIL / AP)

Sudanese pilgrims embrace as they congratulate each other for performing the annual hajj pilgrimage near the Mountain of Mercy, on the Plain of Arafat, near the holy city of Mecca, Saudi Arabia, Aug 10, 2019. (AMR NABIL / AP)