Lake Winnipeg is a large, 24,514-square-kilometre (9,465 sq mi) lake in central North America, in the province of Manitoba, Canada, with its southern tip about 55 kilometres (34 mi) north of the city of Winnipeg. It is the largest lake within the borders of southern Canada, and it is part of the most undeveloped large watershed of southern Canada.
Lake Winnipeg is the sixth-largest freshwater lake in Canada, but it is relatively shallow (mean depth of 12 m (39 ft)) excluding a narrow 36 m (118 ft) deep channel between the northern and southern basins. It is the eleventh-largest freshwater lake on Earth. The east side of the lake has pristine boreal forests and rivers that are being promoted as a potential United Nations World Heritage Park. The lake is elongated in shape and is 416 km (258 mi) from north to south, with remote sandy beaches, large limestone cliffs, and many bat caves in some areas. Manitoba Hydro uses the lake as one of the largest reservoirs in the world. There are many islands in the lake, most of them undeveloped.