Got this link from my friends in the Edmonton area. The video is over 32 minutes long, and every bit of it is worth it. If you like 1970s era railroading, complete with some of the best sounds I've heard in HO (and for that matter, O), check it out. By virtue of #1 in CN livery, the time would be pre-1977. My favorite sequence starts at 16:58, with two freights meeting at Exlou.
Regards,
Jerry