What part of Canada borders Idaho?

Answer 1

the international boundary commission says it is 45 miles or 72 kilometers

but that is a difference of about 1380 feet

& if you want to know which is the better guess

then consider that the great circle arc distance between the 2 end points of the border is much closer to 72 kilometers than to 45 miles

however

unless you actually measure & add the distances between all 29 of the individual boundary markers that stand upon & define the border

you cannot begin to venture the best possible guess at the true length of the border

&

even if you did all that

you would still have to guess rather more wildly at the lengths of the 2 terminal segments between the final markers near both ends of Idaho & the actual tripoints with Montana & Washington respectively

which are in fact not marked by any international boundary markers at all

but are only known & findable by their approximate geocoordinates

so you may have to be content to know that the true length is most probably very nearly exactly 72 kilometers

but at least several hundreds of feet less than 45 miles

Answer 2

The only two states that share a border with both Idaho and Canada are Washington and Montana.

Answer 3

Yes, the northern sliver of Idaho borders Canada.

Answer 4

A few feet over the border.