The world's largest form of mass religious tourism takes place at the annual Hajj pilgrimage in Mecca, Saudi Arabia. North American religious tourists comprise an estimated billion of this industry.
Modern religious tourists are more able to visit holy cities and holy sites around the world. The most famous holy cities are Jerusalem, Mecca, and Varanasi. The most famous holy sites are the Church of Nativity, The Western Wall, Brahma Temple at Pushkar, and the Kaaba. Religious tourism has existed since antiquity, and unlike commercial tourism, is not done for exclusively hedonistic purposes. A study in 2011 found that pilgrims visited Jerusalem for a few reasons: to understand and appreciate their religion through a tangible experience, to feel secure about their religious beliefs