What travelers say
Its very young population is around 14 million people.
The official and most popular language in Tehran is Persian (in Persian it is called Farsi or Parsi). A lot of people, mostly the younger ones speak and write English fluently.
Iran has its own calendar system, the Iranian/Persian calendar system called “Jalali”. This calendar is used in daily life and commerce, although the Iranians are familiar with the western calendar they use it only if they are doing business with the west.
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