Passengers wait for the train at Taizicheng station of the Beijing-Zhangjiakou high-speed railway line in Chongli district of Zhangjiakou City, north China's Hebei Province, Dec. 29, 2020. The railway line has received more than 6.8 million passengers since it was put into service on Dec. 30, 2019. (Xinhua/Li Xin)
