The Canadian transmission networks extend over . The grids generally follow north-south orientations since most population centres in Canada are concentrated in southern regions along the American border while the largest hydroelectric and nuclear projects are located in sparsely inhabited areas to the north. This particular situation forced Canadian utilities to innovate. In November 1965, Hydro-Québec commissioned the first 735-kV AC power line linking the Manic-Outardes project to the Lévis substation. In 1972, Manitoba Hydro connected generating stations part of the Nelson River Hydroelectric Project to the Winnipeg area through a high-voltage direct current power line, the Nelson River Bipole.