The History and Oddities of the US-Canada Border
CGP Grey · Explainer · 5 min · 2013 · YouTube title: The US-Canada Border Is 5,500 Miles of Pure Nonsense
Why it's here
HN recommends it as an entertaining overview in any thread about border oddities.
What it covers
CGP Grey walks through the odd history and quirks of the US-Canada border, including how it was surveyed and its irregularities such as exclaves.