Sanborn fire insurance maps are detailed property and land-use records covering more than 12,000 U.S. towns and cities. Founded in 1867 by D. A. Sanborn,
the Sanborn Map Company was the primary American publisher of fire maps for over 100 years, repeatedly mapping towns and cities as they changed.
"uses a selection of images from Digital Sanborn Maps... images are georeferenced, or assigned geographic coordinates, that enable individual map records
to be found via an address or GPS search. ... layer maps from different years on top of each other and over modern street, satellite, and hybrid layers."--Scope of the collection.