Lac Guillaume-Delisle, 712 km2, is a large, triangular, saltwater lake in northern Québec, connected to the eastern shore of Hudson Bay by Le Goulet, a 5 km long narrow channel. The treeline begins a few km north and the many islands that litter the southern portion of the lake are wooded. The area was visited seasonally by Inuit and Innu, especially at 2 rivers (Petite and Grande Rivière de la Baleine) a short distance to the south, where beluga whales congregate in the summer. The lake was originally called Richmond Gulf by the Hudson's Bay Company, which operated a trading post on an island in the 1750s. It was renamed in 1962 after Guillaume Delisle (1675-1726), a French cartographer who is considered the founder of modern cartography.