A waterfall is considered a geological feature that involves the vertical flow of water over a cliff or a steep section of a riverbed. This phenomenon occurs when a river encounters a change in elevation, often due to geological formations like rock layers, eroding softer materials, creating a sudden drop. Waterfalls can vary in size, height, and volume, and they often create beautiful natural landscapes. The erosive force of the water over time can lead to the formation of gorges or deep pools at the base of the waterfall, showcasing the dynamic processes of nature.