>>1311980>>1311635I often look at this map of Chicagoland from 1934, before most expressways and airfields were constructed. The most dense areas outside the city limits are towns situated near the rail line. To this day, most of those towns are dense and walkable. That density travels 35 miles outside the city to the satellite cities, and yet everything away from rail lines is forest and agriculture.
This is my favorite map. It shows a huge metropolitan area right before the dawn of the automotive age. Just look at the text box titled "Every Road Less Than 40 Feet Wide Is a Menace to Human Life". The Chicago Tribune drew this map to advocate for the widening of all major streets to at least 40 feet in the name of public safety.
I had to shrink the image. The full size image is here:
https://imgur.com/tz5yYWZ 