Green Diamond

Initially it operated with Illinois Central 121, the last of the 1930s fixed-consist articulated streamliners built in the United States.

[2]: 23  The Green Diamond required a single consist to operate, departing Chicago for St. Louis in the morning and returning that same evening.

[2]: 22 Conventional equipment with expanded seating capacity replaced the articulated streamliner in 1947.

Amtrak did not continue the Governor's Special, which ended revenue service on April 30, 1971.

"[1]: 31  Motive power was provided by 1,200 hp (890 kW) EMC Winton 201-A 16-cylinder engine.

In June 1968, service between Springfield and St. Louis was discontinued and the remaining segment of the former Green Diamond was renamed the Governor's Special.

Green Diamond with conventional equipment at Kankakee in August 1964
A 1936 postcard promoting the Illinois Central's streamlined Green Diamond