What country has the largest freshwater lake island in the world?

Manitoulin Island (originally Ekaentouton) is a Canadian lake island in Lake Huron, in the province of Ontario. It is the largest freshwater lake island in the world.

The current name of the island is the English version, via French, of the historic Odawa name "Manidoowaaling", which means "cave of the spirit." It was named for an underwater cave where a powerful spirit was said to live.

Manitoulin Island contains a number of lakes of its own. In order of size, its three most prominent lakes are Lake Manitou, Lake Kagawong and Lake Mindemoya. Each of these three lakes in turn have islands within them, the largest of these being Lake Mindemoya's 82-acre Treasure Island, located in the centre of Manitoulin.

The island has an area of 2,766 km2 (1,068 sq mi), making it the 172nd largest island in the world and Canada's 31st largest island. The island separates the larger part of Lake Huron to its south and west from Georgian Bay to its east and the North Channel to the north.

Manitoulin Island itself has 108 freshwater lakes, some of which have their own islands; in turn several of these "islands within islands" have their own ponds. Lake Manitou, at 104 km2 (40 sq mi), is the largest lake in a freshwater island in the world and Treasure Island in Lake Mindemoya is the largest island in a lake on an island in a lake in the world.