High-speed rail connects major cities in southwest China's mountainous regions

"We will vigorously promote Dafang's tourism when we arrive in Chengdu," said Shang, adding that the launch of the railway line will help promote local tourism as well as the Yi ethnic culture.

Due to the mountainous terrain of the region, about 85 percent of the 648-km-long railway tracks were built on elevated bridges or through tunnels.

"In terms of geological conditions, the Chengdu-Guiyang high-speed rail line is one of the most complicated passenger rail projects in China's mountainous regions," said Zheng Tao, a designer with China Railway Eryuan Engineering Group.

Zheng said completion of the rail line attests to China's advanced know-how in high-speed railway construction, citing engineering feats in the project including ballastless slab track, a long-span steel-concrete basket arch bridge and a steel tube-concrete swivel arch bridge.