Anyone who has ever noticed Minnesota’s little protuberance has to wonder at some point: why on earth would they have drawn the border like that?
The northern border of the lower 48 is flat flat flat along the 49th parallel from Washington State to western Minnesota, and then there’s this thing. If you look closely, the mystery is compounded by the fact that the special included region is uninhabited park land on the far side of a lake.
Is there something valuable there? Gold? Copper? A precious trove of old National Geographics?
The answer is a charming example of fossilized happenstance. The diplomats who negotiated the northwest border of the US had an imperfect knowledge of the region based on this imperfect map. This excellent video from C.G.P. Grey explains all…
Rambles Blog at Star Chamber 
I love the “No touching zone”! As a kid I always assumed there were some kind of stark lines on the ground where countries met, just like on the maps, and here are the US and Canada providing just that!
The narrator’s vocal cadence is hypnotic. I was paying 100% attention. Right up until the phrase “straight-ish line”, with the yellow line bending and straightening out right in time, when I laughed out loud and my attention snapped out to include other things like I should be getting some work done.
Hey! A Minnesota native… what do they teach you about that thing when you’re in fourth grade in Minneapolis?
I do recall being told it had something to do with surveying imprecisions in the post-Revolutionary-War era but that’s about it. No school field trips to the Northwest Angle nor to some dusty library in the basement of Fort Snelling or anything like that.