They made the 8 kilometer journey from Mount Arafat by foot and bus caravan, where they will spend the night, as the Prophet Muhammad did during his own pilgrimage. Millions of people will sleep there in tents.
Hajj rules — based on centuries of interpretation of the Sunna, the traditions of Muhammad — are extremely elaborate. Pilgrims must all gather at certain sites at specific times. Some rites are repeated, others are partially repeated and some performed only once.
Many pilgrims being their journey in the Saudi Arabian city of Medina with a visit to Muhammad’s mosque, where he is buried. They then head to Mecca and perform a set of pre-hajj rituals, including circling the Kaaba counterclockwise with their hearts tilted toward it — the same rituals that conclude the hajj for many.