Maps found on the Google Play Store.
A list is available at:
Old Official Railway Guides by National Association of Timetable Collectors
Maps showing the Indiana & Illinois Central Railway. G.W. & C.B. Colton & Co. 1872
Maps showing the Indiana & Illinois Central Railway. G.W. & C.B. Colton & Co. 1872
1896 B&O Map
Book of Royal Blue
1958 B & O Map
1960 St. Louis Division B & O Map
1970 B & O St. Louis Division Map
1978 Chessie System Map