<P> Roughly 3,500 kilometres ( 2,175 mi ) of the Canada -- United States border was designated to follow the 49th parallel from British Columbia to Manitoba on the Canada side , and from Washington to Minnesota on the U.S. side , more specifically from the Strait of Georgia to the Lake of the Woods . This international border was specified in the Anglo - American Convention of 1818 and the Oregon Treaty of 1846 , however the border as indicated by survey markers placed in the 19th century deviates from the 49th parallel by tens of meters . </P>
<P> Roughly 3,500 kilometres ( 2,175 mi ) of the Canada -- United States border was designated to follow the 49th parallel from British Columbia to Manitoba on the Canada side , and from Washington to Minnesota on the U.S. side , more specifically from the Strait of Georgia to the Lake of the Woods . This international border was specified in the Anglo - American Convention of 1818 and the Oregon Treaty of 1846 , however the border as indicated by survey markers placed in the 19th century deviates from the 49th parallel by tens of meters . </P>
49th parallel is the boundary line between which two nations
49th parallel is the boundary line between which two nations
Canada United States
Canada United States