A five-year-old girl from Lhasa takes a train on Lhasa-Xigaze railway line, southwest China's Tibet Autonomous Region, Aug. 1, 2015. As the first extention line of Qinghai-Tibet railway on the world's highest plateau, Lhasa-Xigaze railway shortens the traveling time from Lhasa to Xigaze to three hours. (Xinhua/Liu Dongjun)

An aid-Tibet worker travels to Xigaze with his son on Lhasa-Xigaze railway line, southwest China's Tibet Autonomous Region, Aug. 1, 2015. As the first extention line of Qinghai-Tibet railway on the world's highest plateau, Lhasa-Xigaze railway shortens the traveling time from Lhasa to Xigaze to three hours. (Xinhua/Liu Dongjun)

Photo taken on Aug. 1, 2015 shows a view of Xigaze railway station in Xigaze, southwest China's Tibet Autonomous Region, Aug. 1, 2015. As the first extention line of Qinghai-Tibet railway on the world's highest plateau, Lhasa-Xigaze railway shortens the traveling time from Lhasa to Xigaze to three hours. (Xinhua/Liu Dongjun)