Originally Posted by PTravel
The OP is travelling from SFO, and I'm pretty sure that there are no direct flights (I go to Edmonton from SFO once or twice a year). Most likely, he'll clear customs in Vancouver or Calgary. Fortunately, I've never had more than a few minutes wait to clear immigration and customs into Canada. Getting back to the US was another story.
In case there is any confusion about this, the situation is basically this:
It is, of course, possible for U.S. Edmonton-bound travellers to clear customs somewhere else in Canada before proceeding to Edmonton (for example, if schedules or frequent flyers plans make this desireable). However, there are direct flights to Edmonton from eight or nine U.S. cities (including San Francisco). One would expect most U.S. travellers to use one of these. In fact, Air Canada is the only option for getting to Edmonton with either a code-share or an inter-line from within Canada, so most U.S. airlines will want to push you through one of those U.S. ports.
Of course, all the aircraft seem to be full these days. Who knows what one's eventual route will be?