As the birthplace of Muhammad, Mecca is the holiest city in the Islamic religion.
At the heart of the pilgrimage is the Grand Mosque which can accommodate up to an astonishing one million worshipers at any one time.
It is worth noting that non-Muslims are strictly forbidden from entering the city at any time and these rules are vigorously enforced.
For several days every year the population of the city more than triples as huge numbers of foreign and local Muslims make the pilgrimage known as the Hajj.
Although prayer is the main purpose of the pilgrimage, many visitors also find time to do a little shopping as there are a number of traditional bazaars and modern shopping malls to explore.
SOURCE: www . mapsofworld . com/travel/infographics/mecca