I've completed adding probable railroad routes to my Twain-Cable tour pages: https://twainsgeography.com/content/twain-cable-tour If you visit, click on "The Tour" option and this will open a page that starts listing the tour dates. Each of the tour date pages (most anyway) have a Google map with a display of the route(s). Most of the routes I've mapped come from the files provided by the University of Nebraska but are no more recent than 1870. There was an explosion of railroad lines between then and 1884-85. I have attempted to improve on the mapping by examining a number of map files provided by the Library of Congress and topographic overlays available on Google Earth. Railway lines failed, were absorbed by other companies, re-routed, etc. And, there is very little if any mention of what lines Twain and Cable took. The tour date pages also have links to pages about the different venues in which they appeared. I would very much appreciate leads to people knowlegable about these topics. This was a critical period in American history. The railroads were possibly the single most significant factor is how and why America became what it is today. The exploding population west of the Mississippi and rapid industrialization occured because the railroads provided the means. Mark Twain was a witness to this.