29 (Xinhua) -- A 219-km high-speed railway line, linking the cities of Zhongwei and Lanzhou in northwest China, entered operation on Thursday.With a designed speed of 250 km per hour, the new railway that connects the Yinchuan-Zhongwei line, has slashed the travel time between Yinchuan and Lanzhou, capitals of Ningxia Hui Autonomous Region and Gansu Province, respectively, to less than three hours.