Relacionar Columnas Stages of a river: features and characteristicsVersión en línea To relate key information about the different parts of a river. por Elvira Garcia Arnal 1 Lower course 2 Upper course 3 Mouth 4 Middle course 5 Source Initial stage of the river. You can find rapids and waterfalls. The water flows more slowly than in the upper course and there are meanders. The start. It is often a place in the mountains. The end. A delta or estuary can be there. The final stage near the coast.