With our lodging in St Mary, trips up to Waterton Lakes National Park in Canada involved a beautiful drive up Chief Mountain International Highway (Rt 17). At this time of the year, customs does not open until 9:00 AM. So for us, the drive through this area occured as the sun was hitting the east side of Glacier National Park - lighting Chief Mountain. Because this border crossing closed for the day in the late afternoon, our return trip was through the Cardston, Alberta customs.