The Masjid al-Ḥarām (, literally "the sacred mosque"), also called the Sacred Mosque, and the Grand Mosque or Great Mosque of Mecca, is the largest mosque in the world and surrounds Islam's holiest place, the Kaaba, in the city of Mecca, Saudi Arabia. Muslims face in the Qibla (direction of the Kaaba) while performing Salat (obligatory daily prayers). One of the Five Pillars of Islam requires every Muslim to perform the Hajj pilgrimage, one of the largest annual gatherings of people in the world, at least once in his or her lifetime if able to do so, including Tawaf (circumambulation) of the Kaaba.