In 2008 User:NE on wikipedia added a bunch of train routes from 1918 to wikipedia:
https://en.wikipedia.org/wiki/Missouri%E2%80%93Kansas%E2%80%93Texas_Railroad#/media/File:Missouri,_Kansas_and_Texas_Railway_system_map_(1918).svg https://en.wikipedia.org/wiki/File:Detroit,_Toledo_and_Ironton_Railroad_system_map_(1918).svg https://en.wikipedia.org/wiki/File:Oregon_and_California_Railroad_system_map_(1918).svg https://commons.wikimedia.org/wiki/File:Michigan_Central_Railroad_system_map_(1918).svg
He says the data for these maps came from "Bureau of Transportation Statistics North American Transportation Atlas Data". Google'ing that I found this:
But that data isn't from 1918.
Archives going as far back as 2011 can be found here:
But 2011 is a far cry from 1918.
So my question is... where can I get train route info going back to 1918?