Engineering technicians lay railway tracks on a grand bridge over the Yarlung Zangbo River in Gyaca County, Shannan City, southwest China's Tibet Autonomous Region, Sept. 20, 2020. Track laying work was carried out here Sunday on a grand bridge of the railway linking regional capital Lhasa and Nyingchi. The 435-km Lhasa-Nyingchi railway, 75 percent of which is bridges and tunnels, has a designed speed of 160 km/h, and is expected to be completed and put into operation in 2021. (Xinhua/Chogo)

Track layer driver Zhao Runze works at the construction site of the track laying on a grand bridge over the Yarlung Zangbo River in Gyaca County, Shannan City, southwest China's Tibet Autonomous Region, Sept. 20, 2020. Track laying work was carried out here Sunday on a grand bridge of the railway linking regional capital Lhasa and Nyingchi. The 435-km Lhasa-Nyingchi railway, 75 percent of which is bridges and tunnels, has a designed speed of 160 km/h, and is expected to be completed and put into operation in 2021. (Xinhua/Chogo)

Engineering technicians lay railway tracks on a grand bridge over the Yarlung Zangbo River in Gyaca County, Shannan City, southwest China's Tibet Autonomous Region, Sept. 20, 2020. Track laying work was carried out here Sunday on a grand bridge of the railway linking regional capital Lhasa and Nyingchi. The 435-km Lhasa-Nyingchi railway, 75 percent of which is bridges and tunnels, has a designed speed of 160 km/h, and is expected to be completed and put into operation in 2021. (Xinhua/Chogo)

Photo shows a grand bridge over the Yarlung Zangbo River built for Lhasa-Nyingchi railway in Gyaca County, Shannan City, southwest China's Tibet Autonomous Region, Sept. 20, 2020. Track laying work was carried out here Sunday on a grand bridge of the railway linking regional capital Lhasa and Nyingchi. The 435-km Lhasa-Nyingchi railway, 75 percent of which is bridges and tunnels, has a designed speed of 160 km/h, and is expected to be completed and put into operation in 2021. (Xinhua/Chogo)

Engineering technicians lay railway tracks on a grand bridge over the Yarlung Zangbo River in Gyaca County, Shannan City, southwest China's Tibet Autonomous Region, Sept. 20, 2020. Track laying work was carried out here Sunday on a grand bridge of the railway linking regional capital Lhasa and Nyingchi. The 435-km Lhasa-Nyingchi railway, 75 percent of which is bridges and tunnels, has a designed speed of 160 km/h, and is expected to be completed and put into operation in 2021. (Xinhua/Chogo)