Hukou Waterfall, a part of the Yellow River, sits at the intersection of northern China's Shanxi and Shaanxi provinces. Recently, the waterfall has become cleaner and clearer due to decreased water flow after adjustments to the reservoir upstream. Once in a while, a rainbow arches across the sky, and the waterfall looks spectacular in its myriad hues. Many choirs often put on shows by the riverbank in front of the waterfall, extolling the strength of the Yellow River.