Web site includes scanned images of nearly every Amtrak system timetable since 1971.
List Of Amtrak Routes (Wikipedia)
Passenger Train Routes In Major Cities
Historic passenger train routings, and those used by Amtrak.
Amtrak Connecting Railroads
Zoomable Google Maps show additional interesting locations, mostly away from the major cities, where Amtrak trains switch between different lines.
Consolidating Amtrak Into Chicago Union Station
Amtrak adopted Chicago Union Station as its main hub outside the Northeast Corridor. And several Amtrak service changes required some interesting routings, in a city which historically had six separate terminal stations for intercity passenger trains.