The hajj pilgrimage is one of the five pillars of Islam, which form the foundation of the religion. The others are the confession of faith, prayer, almsgiving and fasting.
Mecca, and especially the Kaaba and the Great Mosque, is Islam’s holiest place, followed by Medina, where the Prophet Muhammad’s tomb is located, and the al-Aqsa Mosque in Jerusalem.
Several different rituals are performed during the pilgrimage. For example, the pilgrims walk seven times around the Kaaba in the Great Mosque. The devil is also symbolically stoned to death.
The Kaaba is a large cube-shaped building covered in black cloth, which stands in the middle of the courtyard inside the Grand Mosque in Mecca.