Line 9 of Chongqing metro expected to be completed in 2020

Photo taken on Dec. 22, 2017 shows the construction site of a bridge built for Line 9 of the metro system of southwest China's Chongqing Municipality. The Line 9 of Chongqing metro, which is about 32.3 kilometers long, is expected to be completed in 2020. (Xinhua/Wang Quanchao)