The Shiziyang Tunnel is a high-speed railway tunnel under

Shiziyang Shiziyang () or Shizi Channel is the upper channel of the Pearl River estuary. It runs from the confluence of the Dong River and the Pearl River with parts of the Bei River to the Bocca Tigris which separate Lingdingyang the mid channel of ...

, the northern part of the Pearl River estuary in

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

Route

The 10.8 km long tunnel is part of a -long high-speed line from

Guangzhou Guangzhou, Chinese postal romanization, previously romanized as Canton or Kwangchow, is the Capital city, capital and largest city of Guangdong Provinces of China, province in South China, southern China. Located on the Pearl River about nor ...

Shenzhen Shenzhen is a prefecture-level city in the province of Guangdong, China. A Special economic zones of China, special economic zone, it is located on the east bank of the Pearl River (China), Pearl River estuary on the central coast of Guangdong ...

and

Hong Kong Hong Kong)., Legally Hong Kong, China in international treaties and organizations. is a special administrative region of China. With 7.5 million residents in a territory, Hong Kong is the fourth most densely populated region in the wor ...

. It is designed for speeds of up to 350 km/h (usually 250 km/h in operation) - the fastest underwater tunnel in the world. as well as being China's longest underwater tunnel. This allows rail journeys between Guangzhou and Hong Kong to take only 40 minutes – much faster than the previous 2-hour journey. The Guangzhou-Shenzhen-Hong Kong express rail link is part of a broader expansion of high-speed rail in China; journeys from Beijing to Hong Kong will take only 8 hours.

Construction

Construction began in November 2007, with a budget of CNY2.4 billion; the tunnel was completed in 2011, and passenger services began on 26 December 2011. Unusually, the

tunnel boring machine A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. TBMs are an alternative to drilling and blasting methods and "hand mining", allowing more rapid excavation through hard rock, wet or dry so ...

s were designed to be dismantled inside the tunnel.

References

{{coord, 22.86669, 113.55881, dim:10800_type:landmark_region:CN-44, display=title Railway tunnels in China High-speed rail in China Tunnels completed in 2011