Mashhad is the second largest city in Iran after Tehran. It is also globally significant as the resting place of one of Shia Imams and thus considered one of the holiest cities for Twelver Shia Muslims.

Each year more than 15 million pilgrims come to Mashhad to observe the religious rites and if we add a couple of millions who visit Mashhad for reasons other than pilgrimage (mountaineers, businessmen…) the number reaches the staggering 20 million...