At present, the main mode of transportation from Yantai in Shandong province to Dalian in Liaoning province is railway ferry. According to the public data, the Bohai Bay reached 1.01 million vehicles and 6.54 million passengers, of which the Yanlian route reached 890,000 vehicles and 5.62 million passengers in 2011. Marine transportation has undertaken most of the passenger and cargo transportation, but there are significant potential dangers to traffic safety. In order to promote the economic development of Dalian and Yantai better, a cross-sea channel would be established in the Bohai Strait under the sea corridor, Dalian will become the link to South Korea, Japan (China-Japan- Korea Free Trade Zone), the United States (American countries) in the east, to Shenyang, Harbin, Russia and other European countries in the north, and to all parts of southern China. Dalian and Yantai will become transportation hub cities.
According to the Liu Xinhua's basic idea of " Cross-sea channel in the Bohai Strait ", firstly, a railway ferry from Dalian to Yantai should be built to realize the "soft connection" between the two peninsulas. Secondly, a pilot project from Penglai to Changdao should be built to drive large channels by small channels.; finally, the construction of the Submarine Tunnel from Lushun to Penglai will realize the natural moat change thoroughfare in the Bohai Strait.
The Bohai Bay Tunnel requires an investment of more than 260 billion RMB, and reaches a length of 123 kilometers , connecting the Dalian in the north and Yantai in the south. This span will also make cross-sea channel in the Bohai Strait far beyond Japan's Qinghan Submarine Tunnel (about 54 kilometers) and the English Strait Submarine Tunnel (about 51 kilometers), then becomes the world's longest submarine tunnel. The new tunnel will make the transport distance between this two cities be reduced by 1280 kilometers, and it will also form an important part of the high-speed rail network from Northern China to Hainan Island.