closest borderBorder crossing from montreal to united states?

closest border
Answers:   The fastest route to the States is south on highway 15 to Champlain, NY, Plattsburgh and eventually NYC. See and jst look along the border...
route 15 to blackpool
JJ's right. I would add, however, that although that route is indeed the shortest in terms of miles, I've found that long waits (which in some extreme cases can last over two hours) are not uncommon there. Unless you're traveling very early in the morning or late at night, you might consider taking a slight detour to avoid that - perhaps Route 221 (Canadian side of the border) to Route 276 (US side), or Route 219 (Canadian side) to Hemmingford Road (US side).
Everyone's right ... assuming that you're not going to somewhere in particular. If your destination in the States was Watertown or Syracuse, it would be faster to use a port of entry on the 401 such as Cornwall/Massena or Prescott/Ogdensburg.

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