Going to the Sun Highway

wierd, I just looked into the Going to the Sun highway a few days ago, after looking up info on The Shining. It is the road they show from the aerial shots at the beginning of the movie (not Colorado).

You can google it, the US national parks service has lots of info.

The crossing is at Chief Mountain. I'm not sure what you mean by 'expect' at the border crossing, which is quiter compared to places like Coutts/Sweetgrass. It is a normal provincial highway (I think Hwy 6) and becomes a normal two lane road in Montana.
Waterton is a bit of a sleepy place, which adds to the charm, and September will be getting quiet there. Going to the Sun is a very memorable drive, a high mountain road with great views and many switchbacks. They don't allow RVs or vehicles towing large trailers. In mid summer it is thronged with tourists, should be much quieter by September.

I don't think you'll be able to. I think the road is closed for the winter on the Labour Day weekend. We crossed Logan Pass (the Road to the Sun) a few years ago on the last day which happened to be September 1st that year. It was apparent that the weather was iffy as we made our ascent as we passed a small truck mounted snowplow covered coming down. By the time we got to the summit the weather had cleared but the next day it rained like rcazy as we camped, with snow that would have blocked the road at the top.

Its a great drive with fine views but a horror if you have vertigo. tTe last climb before the summit is a continuous series of narrow swithbacks with most of the roadbed on US Army Corps of Engineers built stone buttresses.

It is def worth checking out. We did on motorcycle at the end of Aug and encountered no major problems, and although there were people, it was not crazy busy. You will cross into Montana but I'm not sure where exactly. I would estimate about 1 hour or so from Waterton. If you have the time, you can swing back up into Southern BC (Kimberly and area) which is absolutely beautiful. We did the whole trip in 4 days, driving about 6-8 hrs/day.

The road is gorgeous, one of the most beautiful drives I have taken. We were there mid August and there was certainly no snow yet.

Ditto the above, the road is fabulous. I prefer doing it east to west.

Chief Mtn border crossing can be "iffy", I have had the best of times and the worst of times there. One never knows, haven't been through in a few years now but we used to cross continually and I hear it hasn't changed much, the guards can be in great moods or ugly moods, one never knows. My husband still crosses a lot as he fishes a lot at Duck Lake, Montana and he hasn't had a lot of trouble but the guards all know him well.

Logan Pass (Going to the Sun) is beautiful and is in Montana, not Alberta so it is the USA, well worth the trip if it is open, I believe you can find out about that from the internet, USA parks perhaps. It isn't a long drive (maybe 2 hours? one way on the Logan itself, not including getting there from Waterton) and from St. Mary to West Glacier is the easy trip, coming back, you are on the "cliff" side, if you are uncomfortable with heights and twists and turns, you might want to stay in Montana for the night and come home through Del Bonita or Coutts or perhaps back through Rosseville, BC which is north of Whitefish, Montana. That would take you back into BC between Creston and Fernie.