Tehran’s traffic jams have spawned a curious social phenomenon. The affluent car-driving youth of the northern districts have turned gridlock into a way of meeting members of the opposite sex.

Known as “dor-dor” (“turn-turn” in Farsi), separate groups of young men and women drive around, pulling up alongside each other in congested traffic so they can flirt and pass phone numbers through the window. The cars are either all-girl or all-boy to avoid censorship by the Islamic morality police. If the police do show up they can make a (slow) getaway.

Q&A Where are the next 15 megacities? Show Hide By 2035 another 15 cities will have populations above 10 million, according to the latest United Nations projections, taking the total number of megacities to 48. Guardian Cities is exploring these newcomers at a crucial period in their development: from car-centric Tehran to the harsh inequalities of Luanda; from the film industry of Hyderabad to the demolition of historic buildings in Ho Chi Minh City. We'll also be in Chengdu, Dar es Salaam, Nanjing, Ahmedabad, Surat, Baghdad, Kuala Lumpur, Xi'an, Seoul, Wuhan and London. Read more from the next 15 megacities series here.

Nick Van Mead

This furtive car-cruising is just one of the signs of youthful rebellion against draconian moral codes, and an indication that the Iranian capital might be becoming gradually more relaxed. In Ab-o-Atash park, a teenage girl in skinny jeans and rollerblades allows her headscarf to drop briefly as she coasts past a group of gawping boys. Nearby, a tape of religious music is drowned out by the blaring hip-hop coming from the skatepark. Gaggles of families pose for selfies, while black-cloaked women shuffle past on their way to the mosque.

If we’d been seen out with a boy like this, we would have been forced to marry them Woman in park

“We never had spaces like this when we were growing up here,” says a middle-aged woman visiting from Canada with her sister, where they have both lived for the past 20 years after moving from Iran. “Even a few years ago, a scene like this would have been unthinkable.”

These visions of tolerance and mutual co-existence are a far cry from most foreigners’ preconceived images of Tehran – a place where religious law still forbids women from riding bicycles. On the new Tabiat pedestrian bridge, whose futuristic tendrils wind their way across the valley, young couples sit arm-in-arm, while groups of girls saunter past, their headscarves pulled so far back they seem to defy gravity. “If we’d been seen out with a boy like this,” adds one of the sisters, “we would have been forced to marry them.”

Facebook Twitter Pinterest Taking a selfie on Tabiat pedestrian bridge. Photograph: Oliver Wainwright/The Guardian

This scene of apparent social freedom turns out to be precariously balanced. In 2011, a couple of years after the park opened, 10 people were arrested by the morality police after holding a water fight in the fountains. Two years ago, an extra 7,000 morality police were introduced in Tehran, specifically to monitor the strict hijab rules, targeting everything from loose-fitting headscarves and shortened trousers for women, to glamorous hairstyles and necklaces for men.

Given the capital’s population explosion the authorities face an uphill struggle. From the decks of Tabiat bridge, evening crowds – suspended above the bumper-to-bumper traffic of an eight-lane highway – admire the sunset through a thick haze of smog. Cranes stretch to the horizon, conjuring ever taller concrete towers which march incessantly into the surrounding hills.

Tehran’s population now numbers around 8.4 million people in the city proper, swelling to 14 million in the wider metropolitan region, making it the most populous city in western Asia. It is set to join the global ranks of megacities by 2035, according to forecasts from the UN, with its residents passing the 10 million mark in 2028.

But Tehran is a city on the brink. With some of the world’s highest levels of congestion, air pollution, water shortages, land subsidence and eye-watering costs of living, headscarves should be the least of the authorities’ worries.

Facebook Twitter Pinterest The heavily polluted skyline of Tehran. Photograph: Behrouz Mehri/AFP/Getty Images

Institutionalised bribery

Stuck in traffic on one of Tehran’s interminable freeways, the city can feel like Los Angeles with minarets. The similarity is no coincidence: its modern urban structure was laid out by America’s own doyen of postwar sprawl, Victor Gruen. The godfather of the suburban shopping mall was hired by the Iranian government in 1966 to masterplan the future of the capital, and plotted a web of highways that would thread their way through the undulating topography, connecting a dispersed network of neighbourhoods separated by lush green valleys. The model was typical of American new towns – only adapted to the foothills of the Alborz mountains.

Anyone can pay a fine and build a high-rise. You see highways where they shouldn’t be, shopping malls where they shouldn’t be Masoud Taghavi

It was part of a wave of projects resulting from the American government’s deep engagement with the ruling Pahlavi dynasty. Come the Islamic Revolution of 1979, the masterplan embodied everything that the new regime stood against: it was the detestable legacy of the Shah writ large across the city. Attempts to make a new plan were rejected by the city, so a decision was made to go on with the Gruen scheme, while gleefully rejecting many of its key principles.

The idea of incremental five-year phasing was abandoned in favour expanding the city boundary to its ultimate limits in one go, enabling more land to be developed more quickly to cope with the sudden influx of people. Between 1976 and 1982 Tehran’s population mushroomed by 3 million as families flooded in from the countryside, many fleeing the perilous border regions during the Iran-Iraq war. Inward migration has continued, with internal migrants constituting as much as 88% of the rise in Tehran’s population over the past five years.

There has been a financial incentive behind the city’s expansion too. In the years following the revolution, the municipality realised that a handsome stream of income could be generated by allowing developers to breach the density limits set out in the masterplan in exchange for a substantial fee. Zoning laws were bent and construction permits issued. Revenues collected were then invested in major urban development projects, which in turn increased the value of real estate. The urban form of Tehran was built around a system of institutionalised bribery, which continues to this day.

Facebook Twitter Pinterest Victor Gruen’s 1966 masterplan for Tehran. Photograph: Source: Tehran Municipality

“Anyone can pay a fine and build a high-rise,” says Masoud Taghavi, former editor of Iranian architecture magazine Hamshahri Memari. “There are some plans, but in most cases they’re being ignored. You see highways where they shouldn’t be, buildings where they shouldn’t be, shopping malls where they shouldn’t be.”

The practice of selling density has led to an identikit form of residential development, with plots simply filled to their limits and extruded to maximise the saleable floor area. Most are designed without terraces or balconies and with minimal open space around them.

The policy has also seen a proliferation of huge commercial buildings with little regard to their wider impact. As chairman of Tehran city council’s health and environment committee, Mohammad Haqqani, put it: “Tehran municipality is granting permits to almost all applicants wishing to construct commercial buildings like shopping malls and office buildings, without paying attention to the real needs of each district and the worsening traffic congestion in the sprawling capital.” Following a spate of high-end malls, a district in northern Tehran finally banned their construction last year. But it is too little too late.

Facebook Twitter Pinterest A man walks past a mural in Tehran, part of the city’s beautification scheme. Photograph: Anadolu Agency/Getty

Beautification is skin deep

Many point the finger at Mohammad Bagher Ghalibaf, Iran’s former chief of police and several-time failed presidential candidate, who served as the mayor of Tehran from 2005 until 2017. He presided over a wealth of impressive-looking trophy projects which introduced a glossy image of modernity – but did little to tackle the city’s real problems.

If you making more room for cars, you get more cars on the street. More cars means more congestion and more pollution Ahmadreza Hakiminejad

The expansion of the Sadr expressway was one of his most publicised achievements, seeing a three-mile long double-decker concrete highway erected in the north-east of the city. Articles on the project were greeted with comments such as “Long live Tehran’s master builder, the humble accomplisher, Dr Mohammad Bagher Ghalibaf,” and “May the eyes of the envious and extremist burst in jealousy.”

Those eyes are now watering at the vast expense and unintended consequences of the grand plan, which has had the effect of increasing traffic and further cementing car as king. Members of the Tehran city council conceded last year that adequate research was not conducted before construction began, and that the elevated highway has failed to achieve its main purpose.

“It is a disastrous project,” says architect and urbanist Ahmadreza Hakiminejad. “It was hailed as a way of reducing Tehran’s congestion, but it has had the opposite result. If you make more room for cars, you get more cars on the street. More cars means more congestion and more pollution.”

Facebook Twitter Pinterest Congestion in central Tehran. Photograph: Ebrahim Noroozi/AP

All schools in the capital were forced to close one day last year due to the dangerous levels of toxic particles in the air. Pollution causes an annual 20,000 deaths, according to deputy health minister Alireza Raeisi, a statistic that has even prompted the supreme leader, Ayatollah Ali Khamenei, to weigh in: it is now religiously forbidden to drive vehicles in such high levels of pollution without valid rationale.

Ghalibaf put his efforts into applying a thin layer of decoration across Tehran in an attempt to divert people’s attention from its day-to-day dysfunction. The Bureau of Beautification was established to oversee a campaign of murals, bollard paintings and curious sculptures. A stretch of Valiasr Street now has a sculpture garden along one side, where a number of dead trees have been adorned with artwork to disguise the fact they’re stricken due to lack of water. Bus stops have been decorated and novelty benches commissioned – but nothing has changed beneath the surface.

Hakiminejad says the beautification campaign and the Sadr expressway are just two of innumerable ill-conceived schemes conducted over the last decade, along with policies that have seen the trampling of the city’s little remaining green space. Over the past decade, around 4,000 hectares of Tehran’s former gardens have been destroyed by the so-called “garden tower” act, which allows people to build high-rises on garden land.

Facebook Twitter Pinterest Families ride pedal boats in the artificial Chitgar Lake, to the north-west of Tehran. Critics say there are few facilities such as schools Photograph: Atta Kenare/AFP/Getty Images

Other grand visions, like the satellite development around the artificial Chitgar Lake to the north-west of Tehran, have similarly backfired. The lake has been accused of diverting much-needed flows of water from the city, while the surrounding plots have been sold off in the usual fashion, spawning a grim forest of high-rise towers and malls. There are few of the facilities such as schools that a functioning new urban centre needs.

“It’s yet another ‘wow’ project, designed more as a tourist attraction than an extension of the city,” says Hakiminejad. “It’s going to end up being a vertical slum.”

Chitgar is one of a number of new satellite towns planned across the country in a bid to ease pressure on the capital. Last year the government announced it would build 11 new towns by 2041, a declaration that raised eyebrows given that most of the new towns built after the 1979 revolution remain grossly under-occupied. A total of 17 satellite towns were built on the periphery of Iran’s eight biggest cities in the 1980s and 90s, but most still stand as ghostly dormitories, their vacancy rates at 80%.

And all the time, people keep flocking to Tehran. The Iran Urban Economics Scientific Association estimates that the city’s population now exceeds its capacity by more than 70% – meaning it can only provide 2.3 million of its 8 million residents with decent living conditions. Without wholesale reform of the planning system, real investment in public transport, and an end to the cash-for-towers culture, that statistic stands little chance of improving.

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