Visitors view the Hukou Waterfall of the Yellow River in Yichuan County, northwest China's Shaanxi Province, Sept. 11, 2019. Hukou waterfall is located on the border area between north China's Shanxi and northwest China's Shaanxi provinces. Due to consecutive rainfall, the water volume of Hukou waterfall surged greatly in recent days. (Xinhua/Shao Rui)