China to build world’s largest undersea tunnel

China is set to invest $42bn in a 123km long super tunnel between key regions.

Seikan Tunnel

Japan's Seikan Tunnel Image: Encino

Step aside Seikan and Channel Tunnels and make way for the world’s longest undersea passage: the Bohai Strait Tunnel.

China’s state media has revealed that the government has set aside a massive 260bn yuan ($42bn) to revive plans for construction of a 123km (76.4 mile) long tunnel from the port city of Dalian, Liaoning province, to Yantai city in Shandong.

Plans for the epic tunnel, more than double the size of the world’s current largest undersea tunnel, were first announced in 1994 at a cost of $10bn, but almost 20 years later have failed to get beyond the planning stage. The report has not disclosed a completion date for the project.

The tunnel is expected to shorten the travelling distance between the two northern regions by 620 miles (1000km saving untold travelling hours and potentially generating 20bn yuan in revenue annually.

Japan’s Seikan rail tunnel between Honshu and Hokkaido islands currently holds the crown for longest undersea tunnel at 54km, slightly longer than the Channel tunnel - also for rail only - joining England and France, which is 51km long.