The Kaaba in the centre of the Masjid al-Haram in Mecca, Saudi Arabia, circa 1979. Every year, millions of Muslims complete a hajj or pilgrimage to this sacred spot. (Photo by Keystone/Hulton Archive/Getty Images)
The Kaaba in the centre of the Masjid al-Haram in Mecca, Saudi Arabia, circa 1979. Every year, millions of Muslims complete a hajj or pilgrimage to this sacred spot. (Photo by Keystone/Hulton Archive/Getty Images)