The Laurentian was a named passenger train operated by the Delaware and Hudson Railway between New York City and Montreal, providing same-day daylight service.

[6] By 1964, the D&H, which showed little interest in passenger service after the Second World War, considered discontinuing the Laurentian, prompting an outcry from riders in upstate New York.

[7] The Laurentian survived and received an unlikely upgrade in 1967 at the hands of Frederic C. Dumaine, Jr., the D&H's new president and a proponent of passenger travel at a time when most railroads in the United States were scaling back or abandoning service altogether.

The D&H acquired streamlined ALCO PA diesel locomotives from the Atchison, Topeka and Santa Fe Railway (ATSF) and passenger coaches from the Denver and Rio Grande Western Railroad (D&RGW).

Repainted in the D&H's distinctive blue-silver-yellow livery, the Laurentian cut an impressive figure in its last years, and this equipment remained in use until the start-up of Amtrak on May 1, 1971.