The map above is from a 1920s book about public transportation in the St. Louis area. What I like about it is the way it shows all the little downtowns dotted across the bi-state area (click to enlarge the image).
It would be a fun outing to travel the roads connecting these historic settlements. I wonder how many of them resemble the way they looked back in the 1920s? In between towns, many old farm houses and commercial buildings would still exist.