I kinda had the same question. If I'm correct,
Sanborn was/is an insurance company that has map data for
the areas it serviced (I'm not sure if this includes the
entire US, or is particular to one region).
Close<g>
Sanborn is a map company that used to make maps for insurance companys.
The maps show buildings, water mains, streets, and building information.
ie:
Smith & Smith Flour Mill
Cap 15,0000 Bushels
Lighting Gas
6 in Water Main
Fire protection Hoses & Buckets
No Watchman
Plant power Steam.
This way Smith & Smith's insurance company could save themselves a feild
trip to
check out the building.
Check with your local Library and Historical Society they usually have
Copies of the
maps.
They are also at the Library of Congress & are avilable on microfilm to
educational facilitys
of BIG $$. The set for Minnesota is over $5000, and they would not sell
me a set because
I was not a educational facility.