In this aerial photo taken on Aug. 25, 2018, workers join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region. (Xinhua/Guo Xulei)

As a major constituent of China's high-speed railway network, the 618-kilometer Yinchuan-Xi'an high-speed railway is scheduled to start operation by the end of 2020 with a designed speed of 250 kilometers per hour, and will greatly reduce travel time within Shaanxi, Gansu and Ningxia. (Xinhua/Guo Xulei)

Workers do their jobs to join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region, Aug. 25, 2018. (Xinhua/Wang Peng)

As a major constituent of China's high-speed railway network, the 618-kilometer Yinchuan-Xi'an high-speed railway is scheduled to start operation by the end of 2020 with a designed speed of 250 kilometers per hour, and will greatly reduce travel time within Shaanxi, Gansu and Ningxia. (Xinhua/Guo Xulei)

A worker does his job to join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region, Aug. 25, 2018. (Xinhua/Wang Peng)

As a major constituent of China's high-speed railway network, the 618-kilometer Yinchuan-Xi'an high-speed railway is scheduled to start operation by the end of 2020 with a designed speed of 250 kilometers per hour, and will greatly reduce travel time within Shaanxi, Gansu and Ningxia. (Xinhua/Guo Xulei)

As a major constituent of China's high-speed railway network, the 618-kilometer Yinchuan-Xi'an high-speed railway is scheduled to start operation by the end of 2020 with a designed speed of 250 kilometers per hour, and will greatly reduce travel time within Shaanxi, Gansu and Ningxia. (Xinhua/Guo Xulei)

Workers join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region, Aug. 25, 2018. (Xinhua/Jiang Kehong)

Workers join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region, Aug. 25, 2018.(Xinhua/Jiang Kehong)

Workers join together two girders of the Mafanggou bridge which is part of the Yinchuan-Xi'an high-speed railway in Wuzhong, northwest China's Ningxia Hui Autonomous Region, Aug. 25, 2018. (Xinhua/Jiang Kehong)