You might want to consider cutting south on 22--west of Calgary, thereby missing lots of Calgary traffic. This drive takes you through the heart of Turner Valley, prime ranch country. We stayed several nights in a lovely Lion's Club CG in Black Diamond, giving us an easy drive into Calgary for site seeing but staying in the country. We also thoroughly enjoyed an afternoon at the Bar-U Ranch, a Provincial Historic Site and the largest ranch in Canada at one time. It is on Route 22, just south of Longview. You can go south from the Bar-U to Waterton and then cross into the U.S. near Glacier NP. We have crossed there several times and never had a line. Plus, the scenery at Waterton and then around Glacier NP is equal to anything else you will see on your trip. Don't miss a drive across Glacier on the Going to the Sun road. It's sure to be a highlight.