Dalian undersea tunnel opens to traffic

North China's first immersed tube undersea tunnel, the Dalian Bay Undersea Tunnel, opened to traffic on Monday in Dalian, Liaoning province. The 5.1-kilometer tunnel consists of 18 tubes, each weighing about 60,000 metric tons, and accommodates a two-way six-lane urban expressway.

The 7-kilometer road connecting the tunnel also opened on Monday, reducing travel time from one hour to five minutes and linking the less developed area in the north of the bay to the prosperous business area in the south.

"Ten years have passed since it was determined to be built with the immersed tube process in 2013. It has filled a number of industrial gaps and created a number of records in the field of cross-sea immersed tunnel construction," said Qian Qihu, an academician from the Chinese Academy of Engineering.