Laurentian Divide

[citation needed] From the divide's junction with the Continental Divide at Triple Divide Peak, just south of the U.S. border in northwestern Montana, it runs north to just across the border then east through southern Alberta and Saskatchewan where it turns southeasterly reentering the U.S. at the northwestern corner of North Dakota.

It then continues to the extreme northeast corner of South Dakota before crossing the middle of Minnesota's western border at the Traverse Gap.

The divide then runs north and east through northern Minnesota, through Superior National Forest in the eastern tip, into Ontario.

[citation needed] The eastern portion of the divide marked the original northern boundary of both Ontario and Quebec provinces at the time of Confederation in 1867, although both have since expanded significantly northward.

West of Lake Superior, the divide formed the northern boundary of the United States' Louisiana Purchase in 1803.