Mecca, in western Saudi Arabia, is the birthplace of the prophet Muhammad (c. 570) and was his home until the year 622, when those who opposed him forced him to flee to Medina (a city about two hundred miles north of Mecca). Muhammad later returned to Mecca on his farewell pilgrimage in 632. Mecca is also the site of the Great Mosque, which is situated in the heart of the city. The outside of the mosque is an arcade, made up of a series of arches enclosing a courtyard. In that courtyard is the most sacred shrine of Islam, the Ka’aba, a small stone building that contains the Black Stone, which Muslims believe was sent from Heaven by Allah (God). When Muslims pray (five times a day, according to the Five Pillars of Faith), they face the Ka’aba. It is also the destination of the Hajj, or pilgrimage.