††A reservoir is a large natural or artificial lake where water is stored for an areas' water supply, for irrigation or to produce hydroelectric power. The earliest known man-made reservoir was built by the Egyptians in the Garawi valley around 3000 BC. The dam used to create it was 84m long, 110m wide and 12m high. It was made of earth and stones and the water was probably used for irrigation. Today, the world's largest artificial lake in terms of volume is the Kakhovskaya reservoir on the River Dniepr in Ukraine. It has a volume of 182 cubic kilometres. The world's largest reservoir, measured by area, is Lake Volta in Ghana, which was formed by the Akosombo dam. It was completed in 1965 and has an area of almost 8500 square kilometres.
