A freight train ferry left Lushun in Dalian City, northeast China's Liaoning Province, at 8 a.m. Monday for Yantai, a port city in east China's Shandong Province, marking the start of railway transport across the Bohai Sea.

It is the first train ferry on the Bohai Sea, a horseshoe-shaped sea with an area of 77,000 sq km in north China.

The ferry, a roll-on roll-off vessel 182.6 meters in length and 24.8 meters wide, can carry a 50-car freight train, 50 twenty-ton trucks, 25 passenger cars and 480 passengers.

For the maiden voyage from Lushun to Yantai, the specially built ferry only carried 50 railway cars loaded with cargo such as timber and grain. The ferry is expected to reach Yantai in six hours.

The new service cuts the trip from Yantai to Dalian by 1,800 km. Currently, more than 18 million tons of cargo and 7 million people travel between Dalian and Yantai a year.

It is the second marine ferry service in the country and the longest. China's first rail transport ferry sails the Qiongzhou Strait in south China, connecting Haikou on Hainan Island with Hai'an in Guangdong Province.

Started in 2004, the 3.1 billion yuan (about 387.5 million U.S. dollars) project stretches 159.8 kilometers. The longest in China, it is also the 35th ferry service in the world with a span of more than 100kilometers.

The ferry boat is driven by a special electrical propulsion system being introduced to China for the first time, said the senior management of Sinorail Bohai Train Ferry Co., Ltd, adding that the safe, hi-tech ferry boat had cost 440 million yuan (about 55 million U.S. dollars).

Insiders said the Yantai-Dalian train ferry will foster closer relations among China's three economic circles in the northeast, around the Baihai Sea and in the eastern Yangtze River Delta.

The ferry is a shortcut between northeast China and the country's eastern provinces and is expected to help rejuvenate China's northeastern rust belt.