Engineers work in a tunnel of a coal railway in Sanmenxia, central China's Henan Province, July 11, 2017. The coal railway runs between north China's Inner Mongolia Autonomous Region and Ji'an in east China's Jiangxi Province, linking 7 provinces and regions with a lengh of 1,837 kilometers. The railway is expected to be in operation in 2020. (Xinhua/Zhu Xiang)
