GN “Mountain”-series observation car By Angela Cotey | May 9, 2025 Email Newsletter Get the newest photos, videos, stories, and more from Trains.com brands. Sign-up for email today! Get Updates In 1951 Great Northern received from ACF six remarkable observation-lounge cars to re-equip the Empire Builder. Named for mountains along the train’s route, the cars featured extra-deep windows for better scenery-viewing. GN photo