Work has begun on the new 253km extension of the Qinghai-Tibet railway line, which will link Tibet's capital Lhasa to Xigaze in China.
The planned railway line will run through five counties and over a 90km-long deep canyon in Tibet, to be laid in tunnels or on bridges.
The CNY13.3bn ($1.95bn) rail extension will have the capacity to transport 8.3 million tons of cargo annually and the average speed is 120km per hour.
The rail line will also begin train services in the southwestern Tibetan region, which currently depends only on road transport.
The work will be complete in four years and is the first extension of the railway since it opened in July 2006.
Authorities are also planning to build another railway extension from Lhasa to Nyingchi in southeast Tibet, according to news.xinhuanet.com.