Tehran (/ - , -/,; Persian: تهران Tehrân [tehˈɾɒːn] (listen)) is the largest city in Tehran Province and the capital of Iran. With a population of around 9 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, after Cairo. It is ranked 24th in the world by metropolitan area population.
|تهران بزرگ · The Greater Tehran|
|• Mayor||Alireza Zakani|
|• City Council Chairman||Mehdi Chamran|
|• Urban||615 km2 (237 sq mi)|
|• Metro||2,235 km2 (863 sq mi)|
|Elevation||900 to 1,830 m (2,952 to 6,003 ft)|
|• Density||11,800/km2 (31,000/sq mi)|
|• Population rank in Iran||1st|
|Time zone||UTC+03:30 (IRST)|
|Area codes||(+98) 021|
In the Classical era, part of the territory of present-day Tehran was occupied by Rhages, a prominent Median city destroyed in the medieval Arab, Turkic, and Mongol invasions. Modern Ray is an urban area absorbed into the metropolitan area of Greater Tehran.
Tehran was first chosen as the capital of Iran by Agha Mohammad Khan of the Qajar dynasty in 1786, because of its proximity to Iran's territories in the Caucasus, then separated from Iran in the Russo-Iranian Wars, to avoid the vying factions of the previously ruling Iranian dynasties. The capital has been moved several times throughout history, and Tehran is the 32nd national capital of Persia. 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 locations, 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, a memorial built under the reign of Mohammad Reza Shah of the Pahlavi dynasty in 1971 to mark the 2,500th anniversary of the founding of the Imperial State of Iran, and the Milad Tower, the world's sixth-tallest self-supporting tower, completed in 2007, and the Tabiat Bridge, completed in 2014.
Most of the population are Persian, and roughly 99% of them understand and speak the Persian language, but large populations of other ethnolinguistic groups live in Tehran and speak Persian as a second language.
Tehran has an international airport (Imam Khomeini Airport), a domestic airport (Mehrabad Airport), a central railway station, a rapid transit system, Tehran Metro, a bus rapid transit system, trolleybuses, and a large network of highways.
Plans to relocate Iran's capital from Tehran to another area, due to air pollution and earthquakes, have so far not yet received approval. A 2016 survey of 230 cities across the globe by consultant Mercer ranked Tehran 203rd for quality of life. According to the Global Destinations Cities Index in 2016, Tehran is among the top ten fastest growing destinations.