Thanx, everyone, for this interesting bit of railroadiana.

Here are some links if you want to dig deeper (no pun intended) --
•[..]Google map -- [www.google.com]
•[..]East Dubuque Rail Tunnel -- [johnmarvigbridges.org]
•[..]Gsearch [railroad tunnel east dubuque] -- [www.google.com]
•[..]Images -- [www.google.com]
•[..]Vids -- [www.google.com]