Techniques for street generation in cities

Do you have a contour map of the area?

Only in the roughest sense. It boils down to about five levels of discrete elevation. I'd make a new one with continuous tone if I were going to model it.

I'd like to hear/think more about creating these 3D contour maps, but I'm going to split that off into a separate thread, here. :)

For the record... This was an EXCELLENT post. Thanks for the information keithcurtis. :)

A lot of very good information.