I came across this yesterday and found it pretty interesting:
http://leebyron.com/how/2008/07/13/m...san-francisco/
It basically uses one of those "walkability" sites and uses a heat map to show the more walkable areas.
What is curious is that it tends to follow density maps to some degree, but not entirely. I really want to take a look at the exact methods used by the walkability sites - some areas surprised me and I'd like to figure out why.


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