Staff members of China Railway Seventh Group Co., Ltd. check a bullet train at a maintenance station in Changping District of Beijing, capital of China, Oct. 7, 2019. The maintenance station was put into use as Beijing-Zhangjiakou high-speed railway started joint debugging last week. The high-speed railway is 174 kilometers long, with a maximum design speed of 350 kilometers per hour. The railway line, as a major project for the 2022 Olympic and Paralympic Winter Games, is expected to be finished by the end of 2019. (Xinhua/Ma Ning)