he Cardinal is a three-times-a-week long distance passenger train operated by Amtrak between New York City's Penn Station and Chicago's Union Station, with major intermediate stops at Philadelphia, Washington, Charlottesville, Charleston, Huntington, Cincinnati, and Indianapolis. Trains depart New York on Sundays, Wednesdays, and Fridays, and alternatively depart Chicago on Tuesdays, Thursdays, and Saturdays. The 1,146-mile trip between these two terminals ordinarily takes 26 hours. One of three current Amtrak routes between the Northeast and Chicago (including the Capital Limited) and Lake Shore Limited, the Cardinal's routing is the most southern and the least direct — meandering through southern West Virginia and the river basin of Ohio.

The Cardinal is the successor of several previous trains, primarily the New York Central's (later Penn Central) James Whitcomb Riley and the Chesapeake & Ohio's George Washington. The James Whitcomb Riley was a daytime all-coach train which operated between Chicago and Cincinnati, via Indianapolis; while the George Washington was a C&O sleeper consist that ran between Cincinnati, Washington, and Newport News, Virginia. Both routes survived until the formation of Amtrak in 1971.

The current Cardinal operates over Amtrak's Northeast Corridor, CSX Transportation, Norfolk Southern, Buckingham Branch Railroad, Canadian National Railway, Union Pacific Railroad, and Metra trackage. The Buckingham Branch segment in Virginia makes the Cardinal one of the few Amtrak trains routed over a shortline railroad. Trains ordinarily use standard single-level Amtrak equipment from the Amfleet and Viewliner rosters, pulled by a single locomotive. Because Amtrak's Beach Grove heavy maintenance facility is located near the Indianapolis station, east and westbound Cardinal consists frequently include motive power and passenger equipment moving to and from the shops.