This aerial photo made from a helicopter shows the Abraj Al-Bait Towers with the world’s largest clock face, as Muslim pilgrims circumambulate the Kaaba, the cubic building at the Grand Mosque, durning the hajj pilgrimage in the Muslim holy city of Mecca, Saudi Arabia on Monday. The pilgrimage to Mecca is required once in a lifetime of every Muslim who can afford it and is physically able to make it. (PTI)