All Streets

Ben Fry
All of the streets in the lower 48 United States: an image of 26 million individual road segments. No other features (such as outlines or geographic features) have been added to this image, however they emerge as roads avoid mountains, and sparse areas convey low population. This began as an example I created for a student in the fall of 2006, and I just recently got a chance to document it properly.
Alaska and Hawaii were initially left out for simplicity's sake, but I felt guilty because of the sad emails received from zipdecode visitors. Unfortunately, the two states don't "work" because there aren't enough roads to outline their shape, so I left them out permanently. More technical details can be found here and additional updates here.

San Francisco

A detail of the West shows the relative lack of roads in mountainous areas, punctuated by the densely populated Bay Area.

United States

Original image of the lower 48 states.

The Great Lakes

Chicago and the shore on the left, Detroit to the right: a wonderful range of sparse and complex in this crop.

Appalachian Mountains

The ridges of the Appalachian mountain range emerge from the roads that avoid them (or follow their contours).