A key railway, linking central China' s Hubei Province and southwestern Chongqing municipality, began a seven-day trial operation Wednesday.

Yichang-Wanzhou Railway, linking Hubei' s Yichang City and Chongqing' s Wanzhou District, is a key part of China' s railway system. After being put into operation, the railway will cut the travel time from Wuhan City, capital of Hubei Province, to Chongqing from 22 hours to five hours, said Zhang Mei, head of the Ministry of Railway' s Center of Engineering Management.

Also, the travel time from some cities in central and southwest China to eastern Nanjing and Shanghai cities will be cut to five to nine hours, Zhang added.

The 377-kilometer railway is considered one of the most difficult to build in China as it runs through a rugged region where the Yunnan-Guizhou Plateau meets the Yangtze River Plain.

The railway includes 159 tunnels and 253 bridges. In the most extreme case, it took nearly six years to drill a tunnel through Qiyue Mountain along the route.

Yichang-Wanzhou Railway is also China' s most expensive railway in terms of cost per kilometer. It cost about 60 million yuan to build each kilometer of the railway, compared to 29 million yuan (US$4.37 million) for each kilometer of the Qinghai-Tibet Railway, which is also renowned for its construction difficulties.

The railway started construction in 2003 and was completed in Aug. 2010.

(Xinhua News Agency November 18, 2010)