Tehran is the capital of Iran and Tehran Province. With a population of around 8.4 million in the city and 15 million in the larger metropolitan area of Greater Tehran, Tehran is the most populous city in Iran and Western Asia, and has the second-largest metropolitan area in the Middle East. It is ranked 29th in the world by the population of its metropolitan area.
Tehran was first chosen as the capital of Iran, Large scale demolition and rebuilding began in the 1920s, and Tehran has been a destination for mass migrations from all over Iran since the 20th century.
Tehran is home to many historical collections, including the royal complexes of Golestan, Sa’dabad, and Niavaran, where the two last dynasties of the former Imperial State of Iran were seated. Tehran’s most famous landmarks include the Azadi Tower, and the Milad Tower, the world’s sixth-tallest self-supporting tower which was completed in 2007. The Tabiat Bridge, a newly-built landmark, was completed in 2014. The majority of the population of Tehran are Persian-speaking people.
Tehran has an international airport (Imam Khomeini Airport) , a domestic airport (Mehrabad Airport), a central railway station, the rapid transit system of Tehran Metro, a bus rapid transit system, trolleybuses, and a large network of highways.
October 6 is marked as Tehran Day based on a 2016 decision by members of the City Council, celebrating the day when the city was officially chosen as the capital of Iran by the Qajar dynasty back in 1907.