"Shenzhen-Zhongshan Link": The Pearl River Delta is becoming more interconnected

The Pearl River Delta in the Guangdong Province in southern China is one of the most densely populated regions in the world, with around 120 million inhabitants. The area includes not only the world-famous cities of Hong Kong and Macau, but also nine other major cities with millions of inhabitants. But the “pearl” at the mouth of the Pearl River is the so-called “Greater Bay Area”: It combines the financial center of Hong Kong, the high-tech stronghold of Shenzhen and the manufacturing city of Guangzhou, as well as numerous “unknown” agglomerations in between. Controlled by the firm hand of the Chinese Communist Party, the region is developing as rapidly as it is impressively transforming itself into a global technology hub. It currently has an economic output of 1.8 trillion euros. Status: growing!

A bay with a global reputation and high aspirations?

The entire region has set itself the ambitious goal of becoming a world-leading economic area through cooperation and technological innovation. Each city has its own focus in a “division of labor” to reach the top together.

While Hong Kong has traditionally served as a connecting link and air freight hub between China and the West, Guangzhou shines with its transformation from a production site for cheap goods to a center for high-quality manufacturing of industrialized goods. The provincial capital is particularly strong in the automotive electronics and chemical industries.

Macau, best known for its role as the “Las Vegas of Asia”, is also striving to diversify its economy by uniting tourism, gambling and the entertainment industry, as well as becoming a global center for art and culture.

Doubly young and innovative: Shenzhen

Shenzhen, on the other hand, has a completely different focus: With innovations in the field of artificial intelligence and electromobility, it is home to companies such as Huawei, Tencent and drone manufacturer DJI. The city is considered an innovation hotspot and it is not surprising that it attracts talent from all over the country, making it the “youngest” and richest city in China. The “young” here refers to both the average age, which at under 30 is very low even by Chinese standards, and the age of the city itself. Less than a hundred years ago, Shenzhen was a small fishing village in the hilly coastal region with a few thousand inhabitants. However, development picked up speed particularly in the 1980s, and the city now has a population of over 17 million.

Underwater, above water, and on artificial islands

The Shenzhen-Zhongshan Link is the third direct connection across the Pearl River Delta, alongside the older (and shorter) Humen Bridge to the north and the world’s longest sea bridge between Hong Kong and Macau (31 kilometers long!). Although the Hong Kong-Zhuhai-Macau Bridge is in a class of its own and a construction of absolute superlatives, the Shenzhen-Zhongshan Link is in no way inferior when it comes to technical complexity: The crossing also consists of several bridges, underwater tunnels and artificial islands.

Why did the river crossing need to be built anyway? The old Humen Bridge is located almost 60 km from the Hong Kong-Zhuhai-Macau Bridge, and Shenzhen is exactly in the middle. Zhongshan is on the opposite bank, with the Pearl River Delta separating the two metropolises. Before, if you wanted to travel from one city to the other, you had to drive far inland or to the coast. With the “Link”, the travel time is reduced considerably.

A drone flight along the Shenzhen-Zhongshan link

What the river divides must be brought together

The Shenzhen-Zhongshan Link was opened on June 30, 2024, after a construction period of just over seven years and a cost of around 4.83 billion US dollars. The combination of two bridges and a tunnel creates a 24-kilometer-long direct connection between the two cities. The tunnel portals are located on artificial islands on either side, which in turn are connected to the mainland by suspension bridges.

What is also surprising is that this is not a link with just one lane in each direction. Unlike the Brenner Base Tunnel, for example, which only consists of a single tube, the Shenzhen-Zhongshan Link has eight lanes. The result: Speeds of up to 100 km/h (62 mph) are possible, reducing the journey from nearly two hours to just 30 minutes.

Creative world records of a special kind

It wouldn’t be China if numerous world records hadn’t been set during the construction of every spectacular project. In this case, some of the records seem forced and are related to special construction methods, special floor coverings or somewhat “unusual” aspects such as the thickest concrete pillar in the world. Nevertheless, the Shenzhen-Zhongshan link is more than impressive: For example, it sets the world record for the highest roadway on a sea bridge (91 meters) and is “home” to the world’s first underwater highway interchange.
Yes, you read that right: an entire highway interchange under water – and that’s on an eight-lane road connection!

“Autobots” are securing this marvel

The safety measures also go beyond the usual scope. In the event of a fire, special high-performance fans protect drivers in the tunnel from smoke poisoning . A rather “unusual patrol” consisting of 14 robots monitors the tubes and cable shafts to ensure safe operations. The robots also register car accidents and – thanks to built-in loudspeakers – immediately direct traffic past the scene of the accident. Of course, they also transmit live videos to the control center so that traffic can be monitored in real time.

Lights of different colors on the tunnel walls serve to keep all road users informed. When everything is running normally, the lights are green. In an emergency, however, they turn red to warn drivers of unexpected incidents.

Milestones in the construction