The last time I did so from the continental US was back in 1999 when all they wanted was a drivers license and to make sure you only had a few packs of smokes on you. I understand now that you need a passport to enter into Canada, but do you need a passport if you’re only seeking passage to another part of your own country? I really can’t see one being able to make some sort of declaration to customs that “I demand free passage to the great frozen north of our fine country” or some such twaddle actually working, but is there some sort of provision that allows free travel between Americas?