China's Ministry of Railways has announced plans to add nearly 20,000km of new rail tracks in the country's western region by 2020.
This will give the region a total rail network of 50,000km.
Under the plan, under-construction rail projects will be stepped up and new projects such as the Chengdu-Guiyang railway, Chongqing-Guiyang railway and Kunming-Nanning railway will be started.
The western region has a population of nearly 370 million and occupies 71.4% of the country's total land area.
The cost of the project has not been disclosed.
Overall, the country will spend an average of $102bn (CNY700bn) a year on rail construction over the next three years to achieve its target of a 120,000km national rail network by 2020.