Caption: A Canadian National eastbound off the Prince George line is about to enter the Albreda subdivision at Mileage 70.6 Spicer, British Columbia, on September 26, 1997, and continue east towards Jasper.

Before the construction of new connecting lines in this area, the train would have continued east on the Tete Jaune sub, joining the Montreal - Vancouver line at Red Pass Junction, Mileage 43.7 of the Albreda sub. New construction eased gradients and allowed movements from west to south. The new Robson Sub from Taverna, twenty miles west of Red Pass Jct on the Prince George line to Charles, Mileage 71.6 of the Albreda sub effectively created almost 28 miles of bi-directional double-track. CN also doubled-tracked the Albreda sub for an additional 1.7 miles, almost to the town of Valemount.

The Grand Trunk Pacific Railway opened the Jasper - Prince George Prince Rupert line in 1914. The Canadian Northern Railway's line from Edmonton to Vancouver also used the Yellowhead Pass west of Jasper. This line opened in January 1915. Their consolidation into the Canadian National Railways led to the early removal of considerable duplicate trackage between Edmonton and Red Pass Junction. Traffic growth in resource-rich Western Canada led to the installation of lengthened sidings, double track and the new lines near Mount Robson.

GMDD in London, Ontario, delivered 5712 (#956616-87) as one of 105 SD75Is in 1996 in CN class GF-643a. Repeat orders in 1997 and 1999 brought the total of these units to 175. They feature a 16 cylinder 710 series diesel rated at 4,300 horsepower. The "I" in the model designation indicates the optional "Whisper Cab" that isolated the crew from much track and engine-related vibration. This feature makes them still popular with trains crews. The SD75Is were the first units purchased by the newly privatized CN.