A highway section started a trial operation Saturday, marking the completion of China's east-west trunk line linking Shanghai to Chongqing.

The 320-km-long Hurongxi Section, in Hubei Province, finally joined up the 1,900-km-long Shanghai-Chongqing National Highway, reducing trip between the two destinations to 17 hours.

Construction of the section started seven years ago, during which workers erected 370 bridges, dug 46 tunnels and paved roads through steep mountain ranges by overcoming rare technical difficulties.

The project, involving 20.4 billion yuan (3 billion U.S. dollars) in investment, also greatly saved travel hours and improved traffic conditions in Hubei.