I have attempted to identify and map the railroads Twain rode on during 
his American Vandals tour.  This is tricky because the lines he took are 
rarely identified.  Another problem is the temporal aspect.  They all 
change their names, lease themselves or sell themselves.  Most of these 
lines are from the USGS quads, which may be decades later than Twain's 
travels and are often divisions within a larger railroad, ie the 
Pennsylvania or the Boston & Maine, etc..  The mapped lines are 
clickable as are the cities.

American Vandals Tour - 
https://www.google.com/maps/d/viewer?mid=1-BaTbGlSotYzuWGmkHB8nE0vMWKeawA&usp=sharing 

-- 
/Unaffiliated Geographer and Twain aficionado/