Photo taken on Sept. 4, 2019 shows a scenery of the Grand Canal in Tongzhou District, sub-center of Beijing, capital of China. The Grand Canal, almost 3,200 kilometers in total length, is the world's longest man-made waterway, stretching from Beijing to Hangzhou, capital of east China's Zhejiang Province. It has a history of more than 2,500 years. In recent years, by dredging rivers and pollution control, the Grand Canal has become an important flood control, drainage and landscape river channel in the sub-center of Beijing. (Xinhua/Jin Liangkuai)