A waterfall is a natural landscape feature where water flows over a vertical drop or a series of steep drops in the course of a stream or river. Waterfalls are created as streams flow from soft rock to hard rock, eroding the softer rock more rapidly and creating a plunge. They vary in size and shape, from small cascades to towering falls like Niagara or Angel Falls. The sound of rushing water and the mist created as water crashes into the pool below are common features, making waterfalls popular destinations for their beauty and calming atmosphere.