The Chengdu-Guiyang railway in Qingzhen in southwest China's Guizhou Province, Dec. 15, 2019. (Xinhua/Yang Wenbin)

The rail line links Guiyang and Chengdu, two transport hubs in southwest China, providing vast numbers of passengers in the region a speedy pathway to eastern and southern coastal regions.

At 8:28 a.m. Monday, a bullet train departed Guiyang, capital of southwest China's Guizhou Province, for a largely mountainous journey that will end in Chengdu, capital of Sichuan Province.

With a design speed of 250 km per hour, the train service marked the launch of 648-km-long Chengdu-Guiyang high-speed rail line, an important part in China's ambitious plan to build a high-speed railway network across the country.

The Chengdu-Guiyang railway in Qingzhen in southwest China's Guizhou Province, Dec. 15, 2019.(Xinhua/Yang Wenbin)

The rail line links Guiyang and Chengdu, two transport hubs in southwest China, providing vast numbers of passengers in the region a speedy pathway to eastern and southern coastal regions, said Li Yi, a main designer of the railway with China Railway Eryuan Engineering Group.

"The railway is of key significance for tourism, mineral exploitation, poverty alleviation, as well as China's strategy to develop the western region," said Li.