Laborers work at the construction site of the Datong-Zhangjiakou high-speed railway in Tianzhen County, north China's Shanxi Province, June 19, 2018. The 140-kilometer railway, connecting Datong of Shanxi Province and Zhangjiakou of Hebei Province in north China, is designed for a maximum speed of 250 kilometer per hour. Its construction is expected to be finished by the end of 2019. (Xinhua/Yang Chenguang)