Tehran is the capital of Iran and Tehran Province. With a population of around 9 million in the city and 16 million in the wider metropolitan area, Tehran is the largest city and urban area of Iran, the 2nd-largest city in Western Asia, and the 3rd-largest in the Middle East. It is ranked 29th in the world by the population of its metropolitan area.

In the Classical era, part of the present-day city of Tehran was occupied by a Median city which in the Avesta occurs as Rhaga. It was destroyed by the Mongols in the early 13th century, and remains now as a city in Tehran Province, located towards the southern end of the modern-day city of Tehran.

Tehran was first chosen as the capital of Iran by Agha Mohammad Khan of the Qajar dynasty in 1796, in order to remain within close reach of Iran's territories in the Caucasus, before being separated from Iran as a result of the Russo-Persian Wars, and to avoid the vying factions of the previously ruling Iranian dynasties. The capital has been moved several times throughout the history, and Tehran is the 32nd national capital of Iran.

The city was the seat of the Qajars and Pahlavis, the two last imperial dynasties of Iran. It is home to many historical collections, such as the royal complexes of Golestan, Sa'dabad Complex, and Niavaran Complex, as well as the country's most important governmental buildings of the modern period.

Large scale demolition and rebuilding began in the 1920s, and Tehran has been a destination for the mass migrations from all over Iran since the 20th century.

The most famous landmarks of the city include the Azadi Square, a memorial built during the Pahlavi period, and the Milad Tower, the world's 17th tallest freestanding structure which was built in 2007. Tabiat Bridge, which was completed in 2014, is considered the third symbol of the city.

The majority of the people of Tehran are Persian-speaking people, and roughly 99% of the population understand and speak Persian; but there are also large populations of other Iranian ethnicities in the city such as Azerbaijanis, Armenians, Lurs, and Kurds who speak Persian as their second language.

Tehran is served by the Mehrabad and Khomeini international airports, a central railway station, the rapid transit rail system of the Tehran Metro, as well as a trolleybus and a BRT system, and has a huge network of highways.

There have been plans to relocate Iran's capital from Tehran to another area; due mainly to air pollution and the city's exposure to earthquakes. To date, no definitive plans have been approved. A 2016 survey of 230 cities by consultant Mercer ranked Tehran 203rd for quality of living.


History:

The origin of the name Tehran is uncertain. The settlement of Tehran dates back over 7,000 years.

Classical era

The present-day city of Tehran was a suburb of an important Median city which was known as Rhaga in Old Persian. In the Avesta's Videvdat (i, 15), Rhaga is mentioned as the twelfth sacred place created by the Ohrmazd. In Old Persian inscriptions, Rhaga appears as a province (Behistun 2, 10–18). It was a major area for the Iranian tribes of Medes and Achaemenids. From Rhaga, Darius the Great sent reinforcements to his father Hystaspes, who was putting down the rebellion in Parthia (Behistun 3, 1–10). In some Middle Persian texts, Rhaga is given as the birthplace of Zoroaster, although modern historians generally place the birth of Zoroaster in Khorasan. Derived into Modern Persian as Rey, it remains now as a city located towards the southern end of the modern-day city of Tehran, which has been absorbed into the Greater Tehran metropolitan area.

Mount Damavand, the highest peak of Iran which is located near Tehran, is an important location in Ferdowsi's Shahname, the long Iranian epic poem which is based on the ancient epics of Iran. It appears in the epics as the birthplace of Manuchehr, the residence of Keyumars, the place where Freydun binds the dragon fiend Aži Dahāka and the place where Arash the Archer shot his arrow from.

Medieval period

During the Sassanid era, in 641, Yazdgerd III issued his last appeal to the nation from Rey, before fleeing to Khorasan. Rey was dominated by the ParthianMihran family, and Siyavakhsh, the son of Mihran the son of Bahram Chobin, who resisted the Muslim Invasion. Because of this resistance, when the Arabs captured Rey, they ordered the town to be destroyed and ordered Farrukhzad to rebuild the town anew.

There is a temple in Rey which is said to be one of the temples of Anahita, a cosmological figure in Iranian mythology. After the Muslim Invasion, the temple became dedicated to the eldest daughter of Yazdgerd III, Bibi Shahr Banou, who married to Husayn ibn Ali, the fourth leader of the Shia faith.

Tehran was a well known village in the 9th century, but less known than the city of Rey which was flourishing nearby. Najm od Din Razi, known as Daya, declared the population of Rey to be 500,000 before the Mongol Invasion.

In the 10th century, Rey was described in detail by Islamic geographers.Despite the interest that Arabian Baghdad displayed in Rey, the number of Arabs in the city remained insignificant and the population mainly consisted of Persians of all classes. The Oghuz Turks invaded Rey discretely in 1035 and 1042, but the city was recovered during the Seljuq and Khwarazmian eras.

In the 13th century, the Mongols invaded Rey, laid the city to ruin and massacred many of its inhabitants.Following the invasion, many of the city's inhabitants escaped to Tehran, and the new residence took over its role.

In July 1404, Ruy González de Clavijo, a Castilian ambassador, visited Tehran while on a journey to Samarkand, the capital of Timur, who ruled Iran at the time. Clavijo later described Tehran as an unwalled region under the Timurid Empire.

Early modern era

When the Italian traveler Pietro della Valle passed through the city overnight in 1618, he mentioned it as "Taheran" in his memoirs, while Thomas Herbert mentioned it as "Tyroan." Herbert stated that the city had 3,000 houses in 1627.

In the early 18th century, Karim Khan of the Zand dynasty ordered a palace and a government office to be built in Tehran, possibly to declare the city his capital, but he later moved his government to Shiraz. Eventually, the Qajar king Agha Mohammad Khan was the first to choose Tehran as the capital of Iran in 1776.

Agha Mohammad Khan's choice of his capital was based on a similar concern for the control of both the northern and the southern regions of Iran. He was aware of the loyalties of the inhabitants towards the previous capitals, Isfahan and Shiraz, to the Safavidand Zand dynasties respectively and was wary of the power of the notable people in these cities. He probably viewed Tehran's lack of a substantial urban structure as a blessing, because it minimized the chances of resistance to his rule by the notables and by the general public. Moreover, he had to remain within close reach of Azerbaijan and Iran's integral Caucasian territories in the North and South Caucasus, at that time not yet irrevocably lost per the treaties of Golestan and Turkmenchay to the neighboring Imperial Russia, which would follow in the course of the 19th century.

After 50 years of Qajar rule, the city still barely had more than 80,000 inhabitants.

Up until the 1870s, Tehran consisted of a walled citadel, a roofed bazaar, and sharestan, where the majority of the population resided in the three main neighborhoods of Udlajan, Chale Meydan, and Sangelaj. The first development plan of Tehran in 1855 emphasized the traditional spatial structure. Architecture, however, found an eclectic expression to reflect the new lifestyle.

The second major planning exercise in Tehran took place under the supervision of Dar ol Fonun. The map of 1878 included new city walls, in the form of a perfect octagon with an area of 19 square kilometers, which mimicked the Renaissance cities of Europe.

Late modern era

As a response to the growing social awareness of civil rights, on June 2, 1907, the first parliament of the Persian Constitutional Revolution passed a law on local governance known as the Baladie Law. The second and third articles of the law, on Baladie Community (or the city council), provided a detailed outline on issues such as the role of councils within the city, the members' qualifications, the election process and the requirements to be entitled to vote.

After the First World War, Reza Shah immediately suspended the Baladie Law of 1907, and the decentralized and autonomous city councils were replaced by centralist approaches of governance and planning.

From the 1920s to 1930s, the city was essentially rebuilt from scratch, under the rule of Reza Shah Pahlavi. Reza Shah believed that ancient buildings such as large parts of the Golestan Palace, Tekye Dowlat, the Toopkhane Square, the city fortifications and the old citadel among others, should not be part of a modern city. They were systematically demolished, and modern buildings in the pre-Islamic Iranian style, such as the National Bank, the Police Headquarters, the Telegraph Office and the Military Academy were built in their place. The Grand Bazaar was divided in half and many historic buildings were demolished in order to build wide straight avenues in the capital. Many Persian gardens also fell victim to new construction projects.

The changes in the urban fabric started with the street-widening act of 1933 which served as a framework for changes in all other cities. As a result of this act, the traditional texture of the city was replaced with cruciform intersecting streets creating large roundabouts, located on the major public spaces such as the bazaar.

As an attempt to create a network for the easy movement of goods and vehicles in Tehran, the city walls and gates were demolished in 1937 and replaced by wide streets cutting through the urban fabric. The new city map of Tehran in 1937 was heavily influenced by the modernist planning patterns of zoning and gridiron networks.

During the Second World War, Soviet and British troops entered the city. Tehran was the site of the Tehran Conference in 1943, attended by U.S. President Franklin D. Roosevelt, Soviet Premier Joseph Stalin, and British Prime Minister Winston Churchill.

The establishment of the planning organization of Iran in 1948 resulted in the first socio-economic development plan to cover 1949 to 1955. These plans not only failed to slow the unbalanced growth of Tehran, but with the 1962 land reforms that Mohammad Reza Shah Pahlavi called the White Revolution, Tehran's chaotic growth was further accentuated.

To bring back order to the city and resolve the problem of social exclusion, the first comprehensive plan of Tehran was approved in 1968. The consortium of Iranian consultants Abd ol Aziz Mirza Farmanian and the American firm of Victor Gruen Associates identified the main problems blighting the city to be high density suburbs, air and water pollution, inefficient infrastructure, unemployment and rural-urban migration. Eventually, the whole plan was marginalized by the 1979 Revolution and the subsequent Iran–Iraq War.

Tehran's most famous landmark, the Azadi Tower, was built by the order of the Shah in 1971. It was designed by Hossein Amanat, an architect who won a competition to design the monument, using Sassanid and Achaemenid elements. Formerly known as the Shahyad Tower, it was built in commemoration of the 2,500 year celebration of the Persian Empire.

Throughout the 1960s and 1970s, Tehran was rapidly developing under the reign of Mohammad Reza Pahlavi. Modern buildings altered the face of Tehran and ambitious projects were envisioned for the following decades. The majority of these projects, such as the Milad Tower, were continued after the 1979 Revolution when Tehran's urbanization had reached its peak, and the new government started many other new projects.

During the 1980–88 Iran–Iraq War, Tehran was the target of repeated Scud missile attacks and air strikes.

The 435-meter-high Milad Tower was completed in 2007, and has become a landmark of the city of Tehran. The 270-meter pedestrian overpass of Tabiat Bridge is another landmark of the city, which was designed by the award winning Leila Araghian and was completed in 2014.


Geography:

Location and subdivisions

Tehran County borders Shemiranat County to the north, Damavand County to the east, Eslamshahr, Pakdasht, and Rey counties to the south, and Karaj and Shahriar counties to the west.

The City of Tehran is divided into 22 municipal districts, each with its own administrative center. 20 of the 22 municipal districts are located in Tehran County's Central District, while the districts 1 and 20 are respectively located in Shemiranat and Rey counties.

Climate

Tehran features a semi-arid climate (Köppen climate classification: BSk) with continental climate characteristics and aMediterranean climate precipitation pattern. Tehran's climate is largely defined by its geographic location, with the towering Alborz Mountains to its north and the central desert to the south. It can be generally described as mild in the spring and autumn, hot and dry in the summer, and cold and wet in the winter.

Because the city is large with significant differences in elevation among various districts, the weather is often cooler in the hilly north than in the flat southern part of Tehran. For instance, the 17.3 km (10.7 mi) Valiasr Street runs from Tehran's railway station at 1,117 m (3,665 ft) elevation above sea level in the south of the city to the Tajrish Square, and at 1,612 m (5,289 ft) elevation above sea level in the north.However, the elevation can even rise up to 1,900 m (6,200 ft) at the end of the Velenjak Street in the north of Tehran.

Summer is long, hot and dry with little rain, but relative humidity is generally low. Average high temperatures are between 35 and 40 °C (95 and 104 °F), and at nights it rarely drops below 23 °C (73 °F). Most of the light annual precipitation occurs from late autumn to mid-spring, but no one month is particularly wet. The hottest month is July, with a mean minimum temperature of 26 °C (79 °F) and a mean maximum temperature of 36 °C (97 °F), and the coldest is January, with a mean minimum temperature of −1 °C (30 °F) and a mean maximum temperature of 8 °C (46 °F).

The weather of Tehran can sometimes be unpredictably harsh. The record high temperature is 43 °C (109 °F) and the record low is −17 °C (1 °F). On January 5 and 6, 2008, after years of relatively little snow, a wave of heavy snow and low temperatures covered the city in a thick layer of snow and ice, forcing the Council of Ministers to officially declare a state of emergency and close down the capital on January 6 and 7.

Tehran has seen an increase in relative humidity and annual precipitation since the beginning of the 21st century. This is most likely because of the afforestation projects, which also include expanding parks and lakes. The northern parts of Tehran are still more lush than the southern parts.

In February 2005, heavy snow covered all of the parts of the city. Snow depth was 15 cm (6 in) in south part of the city and 100 cm (39 in) in the north of city. A newspaper said it had been the worst weather for 34 years. 10,000 bulldozers and 13,000 municipal workers deployed to keep the main roads open.

On February 3, 2014, Tehran reached a heavy snowfall, specifically in the northern parts of the city, with a height of 2 meters. Within the one week successive snowfall roads were made impassable in some areas in north of Tehran along with a temperature variety of -8 °C to -16 °C

On June 3, 2014, a severe thunderstorm with powerful microbursts created a haboob that engulfed the city in sand and dust. Five people were killed and more than 57 injured. This disaster also knocked numerous trees and power lines down. It struck between 5 and 6 PM, plummteing temperatures from 33 °C to 19 °C in just an hour. The dramatic temperature drop was accompanied by wind gusts reaching nearly 118 km/h.

Environmental issues

A plan to move the capital has been discussed many times in prior years, due mainly to the environmental issues of the region. Tehran is rated as one of the world’s most polluted cities, and is also located near two major fault lines.

The city suffers from severe air pollution. 80% of the city's pollution is due to cars. The remaining 20% is due to industrial pollution. Other estimates suggest that motorcycles alone account for 30% of air and 50% of sound pollution in Tehran.

In 2010, the government announced that "for security and administrative reasons, the plan to move the capital from Tehran has been finalized. The Iranian Parliament named Shahroud, Esfahan and Semnan as three of the main candidates to replace Tehran as the capital. There are plans to relocate 163 state firms to the provinces and several universities from Tehran to avoid damages from a potential earthquake.

The officials are engaged in a battle to reduce air pollution. It has, for instance, encouraged taxis and buses to convert from petrol engines to engines that run on compressed natural gas. Furthermore, the government has set up a "Traffic Zone" covering the city center during peak traffic hours. Entering and driving inside this zone is only allowed with a special permit.

There have also been plans to raise people's awareness about the hazards of the pollution. One method that is currently being employed is the installation of Pollution Indicator Boards all around the city to monitor the current level of particulate matter (PM10), nitrogen dioxide (NO2), ozone (O3), sulfur dioxide (SO2), and carbon monoxide (CO).

Tourism

Tehran, as one of the main tourist locations in Iran, has a wealth of cultural attractions. It is home to royal complexes built during the two last monarchical periods of the country, including the GolestanSa'dabad Complex and Niavaran Complex complexes.

There are several historic, artistic and scientific museums in Tehran, such as the National Museum of Iran, Malek Museum, Ferdows Garden, Glassware and Ceramics Museum, Museum of the Qasr Prison, the Carpet Museum of Iran, Museum of Glass Painting (vitrai art) and the Safir Office Machines Museum. There is also the Tehran Museum of Contemporary Art in which works of famous artists such as Van Gogh, Pablo Picasso and Andy Warhol are featured.

Tehran is also home to the Iranian Imperial Crown Jewels, claimed to be the largest jewel collection in the world. The collection comprises a set of crowns and thrones, some 30 tiaras, numerous aigrettes, jewel studded swords and shields, a vast amount of precious loose gems, as well as the largest collections of emeralds, rubies and diamonds in the world. It also includes other items collected by the Shahs of Iran. The imperial crown jewels are on display at the Central Bank of Iran.

Tehran International Book Fair is known to the international publishing world as one of the most important publishing events in Asia.