I guess, for my part, I am still confused as to how big a "square" in Civ parlance might be, as I do suggest further above. It appears though, in the older, developed countries, that you can't go too many hundred square miles without encountering at least a secondary road net, but I'm not going to push the point. Let's all make up. 
In my example of the Everglades however, a large, formerly quite wild "eastern" area; there are now at least three north-south roads running through that now, as well as one lateral secondary and the US41/"Tamiami Trail" and I75/"Alligator Alley," these last two both running near the north boundary and both major arteries. This though most of the "Glades" is still underwater. In "CSI:Crime Scene Investigation," America's most-watched television show for most of the last several years, they frequently do location shots in rural Nevada outside of Las Vegas, for variety and probably as a reward to the state for assisting the show by promoting in a different way its tourism. Filming gear transport may be one consideration, but some of the rural locations have been fascinating and do usually, even for plot purposes, include a road.
However, I don't want to go OT talking about commercial television. I was relying on that impression as, for family reasons, I seldom travel west of the Mississippi. Johnny Depp's film version of "Fear and Loathing in Las Vegas" (1998) also featured some footage of a bare, but existing, rural Nevada road net which may have led me astray.

In my example of the Everglades however, a large, formerly quite wild "eastern" area; there are now at least three north-south roads running through that now, as well as one lateral secondary and the US41/"Tamiami Trail" and I75/"Alligator Alley," these last two both running near the north boundary and both major arteries. This though most of the "Glades" is still underwater. In "CSI:Crime Scene Investigation," America's most-watched television show for most of the last several years, they frequently do location shots in rural Nevada outside of Las Vegas, for variety and probably as a reward to the state for assisting the show by promoting in a different way its tourism. Filming gear transport may be one consideration, but some of the rural locations have been fascinating and do usually, even for plot purposes, include a road.
However, I don't want to go OT talking about commercial television. I was relying on that impression as, for family reasons, I seldom travel west of the Mississippi. Johnny Depp's film version of "Fear and Loathing in Las Vegas" (1998) also featured some footage of a bare, but existing, rural Nevada road net which may have led me astray.
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