Oh my god! I didn't know that the the united states is literally crisscrossed by roads in a relatively square grid fashion, as in [1]. This kind of detail was invisible in the previous version. Here is a frightening image of China [2]. Each of these patches is a town!
I've messed around with building 'road pressure' maps using the Tiger data from the census, in states like Michigan (at least in the lower peninsula), there is very little land that is not within about 1/2 mile of a public road.
A lot of the land in the western U.S. was given out by the government in square plots to anyone willing to settle there and plat some crops/trees. I believe this was under the homestead acts.
This update of the maps is amazing!
[1]https://maps.google.com/?ll=47.115467,-97.306595&spn=0.29298... [2]https://maps.google.com/?ll=38.002656,115.434723&spn=0.67848...