Steady progress has been made in the complicated construction of the Lhasa-Nyingchi Railway – a high-elevation railway in southwest China's Tibet Autonomous Region.

By Monday, construction started on the fourth station on the railway linking the regional capital city of Lhasa and Nyingchi some 400 kilometers away.

The line will have 34 stations.

So far, 90.3 kilometers of the 435 kilometers Lhasa-Nyingchi Railway has been completed. 

The Lhasa-Nyingchi Railway is a section of the Sichuan-Tibet Railway, which will soon become the second railway to Tibet from the inland. Built in four sections – Lhasa to Nyingchi, Chengdu to Ya'an, Ya'an to Kangding, and Kangding to Nyingchi, the Sichuan-Tibet Railway is under busy construction. Once completed, it will shorten the time it takes to get from the inland to Lhasa to around seven to eight hours. 

About 75 percent of the railway on the high plateau are bridges and tunnels, and it is expected to be completed in 2020. 

In building the railway, the workers have to cope with challenges of hypoxia, the long rainy season, and complicated geological conditions. 

"The workers have been braving safety risks as it is very easy for them to become tired after longtime intensive work in the oxygen-deficient environment. Also, wind can blow up to 62-74km/h in the dry, windy season in the Yajiang Valley along the Lhasa-Nyingchi Railway, which also poses risks to workers working at high positions," said Liu Jun, a Party official of the Lhasa-Nyingchi Railway Project of China Railway 11th Bureau Group.