Mulism pilgrims perform prayers around the Kaaba, Islam's holiest shrine, at the Grand Mosque in Saudi Arabia's holy city of Mecca on August 7, 2019, prior to the start of the annual Hajj pilgrimage in the holy city. - Muslims from across the world gather in Mecca in Saudi Arabia for the annual six-day pilgrimage, one of the five pillars of Islam, an act all Muslims must perform at least once in their lifetime if they have the means to travel to Saudi Arabia. (Photo by FETHI BELAID / AFP)