Shenzhen grew up in a futuristic city in just 30 years
Thirty years ago, Shenzhen was a fishing village surrounded by rice fields.
Then came a plan to build China's first special economic zone to allow foreign investment, and out of the tranquil countryside, businesses and private factories grew that eventually became a city.
Now Shenzhen, with a population of 12 million, is only part of a huge urbanized area that descends the Pearl River Delta.
The ambitions of China's smart cities are among the largest in the world. But there is doubt as to whether their surveillance technologies will improve the quality of life of the inhabitants or will only be used to keep them alert.
By 2050, about 292 million Chinese will live in the cities. Already more than 58% of the population are urban dwellers, compared to only 18% in 1980.
According to the authorities, there are 662 Chinese cities, including over 160 with one million people or more.
Recently at the Smart Cities Expo in Barcelona, Shenzhen had one of the largest exhibitions.
One of the biggest focuses of technology in Shenzhen is traffic and how to relieve congestion.
Jiang Wei Dong, general manager of the local delegation, told the BBC that technologies are fueling the city.
They are, he said, "seriously focused on pollution."
"Compared to other cities, Shenzhen is clean," he added.
The city is the first in China to ensure that all buses and taxis on its roads are electric, he explained.
In addition to smarter transportation, there is a new smart health system that ensures that when someone arrives in the city of a distant province, their health records are immediately accessible.
But when asked about security systems, his answer was less enthusiastic.
"We are only familiar with traffic. For the citizens of Shenzhen, there is no monitoring," he said.
But at a separate event in the city itself, the public is being challenged to consider the speed with which surveillance technology is being implemented.
Shenzhen Futian Station is hosting Eyes of the City – an exhibition that asks the question, "What happens to people and the cityscape when the sensor-imbued city is able to look back?"
Eyes of the city
Exhibits at the Eyes of the City show will highlight how smart city technologies are monitoring the public
Among the works on display, there is a facial recognition system that visitors can choose not to wear a special mask and displays that look at ticket holders by analyzing their emotional responses.
"One of the main objectives of the Eyes of the City exhibition is to encourage visitors to position themselves while avoiding the dangerous option of neutrality," said curator Carlo Ratti.
China is creating new cities at an impressive rate, redefining the urban landscape with plans to create 19 gigantic urban sprawl and the world's first super-city with over 40 million inhabitants.
Urban development on this scale will require efficiency. Traffic will have to be controlled to avoid traffic jams that last a week, and transportation will have to be green to avoid killing everyone with CO2 emissions.
But it will also be necessary for the citizens themselves to be more efficient. Littering, playing loud music on a train, crossing the street when the lights are red – they will no longer be small indiscretions and become major inconveniences in such large cities.
In 2014, the idea of a social credit system was presented. The somewhat Orwellian plan is to reward citizens for good behavior and punish them for bad behavior. In March this year, millions of discredited travelers were banned from buying train or plane tickets for various crimes, such as using expired tickets or smoking on a train.
Social credit data leads many to be banned from public transportation
"In China, the whole social scoring experiment is fascinating, but I'm glad I don't have to go through it," said smart city consultant Charles Reed Anderson.
There is currently no unified social credit system. Instead, local governments reinforce the idea in different ways that can sometimes affect foreign visitors.
Anderson told an anecdote about a friend who had recently visited a Chinese city.
"He arrived at the hotel and realized he had left (his taxi phone), so the hotel took him to the police station," he explained.
"The police took the data about the vehicle but did not have the traffic camera and took it to another department a few blocks away. They were able to track the taxi in real time and called the driver to ask him to bring the phone back.
"Within two hours, he retrieved the phone."
"The taxi driver may be concerned that if he didn't return it, he would get a negative score."
Eyes of the city
Facial recognition systems are becoming more prevalent
There has been a lot of criticism of the system, but, Anderson says, it probably seems a lot less daunting to Chinese citizens, who grew up used to monitoring their activities by the state.
"I'm not 100% behind this – it can offer some good things. But if it starts being abused, it becomes a big problem," he said.
Human Rights Watch revealed earlier this year that a social credit system used in Xinjiang province, home to a largely Muslim population, was linked to an application used by Chinese police and other government officials.
More and more data and information is falling into government hands through sensors and other technologies in cities.
But what happens when cities deal with private technology giants like Alibaba and Tencent, who have vast databases of citizen information?
Alibaba is headquartered in the eastern city of Hangzhou and has spent two years developing a platform called City Brain, which analyzes camera data and the GPS location of cars and buses, and uses them to control over 1,000 traffic lights to avoid traffic jams. .
It claims it helped reduce the city to seven million from China's fifth most congested city to 57th on the list.
Now cities are handing over bits of land to technology companies.
The Shenzhen government has just granted Tencent a small piece of 809 square meter (8,708 square foot) reclaimed land to build what it describes as "a future city focused on technology and innovation."
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And increasingly, Western cities are also making deals with Chinese companies.
Advisers in Darwin, Australia traveled to China to meet Huawei and see its technology in Shenzhen. The company has implemented a $ 10 million program to launch 900 smart LED lights, 24 environmental sensors and a network of 138 CCTV cameras.
Rejecting allegations that the city would implement a similar social credit scheme, Mayor Kon Vatskalis told ABC News that "there is no facial recognition … and our cameras don't know who you are or what you do."
You can learn about this and other smart cities at the BBC World Service Business Daily.