Thanks to librarian Lisa Dunseth at the San Francisco History Center for tipping us off that local famed map collector David Rumsey is scanning the library’s 1905 Sanborn Fire Insurance maps. The work is still in progress (our western neighborhoods aren’t represented yet), but it’s mesmerizing to examine the buildings of the city before the 1906 earthquake and fire. Better yet, the scans are in color so the coding that identifies brick and wood-frame is all there. More details from the site’s notes:
A series of six detailed insurance map volumes reflecting the specific building uses and construction types for the City of San Francisco in September 1905. This was just six months before the devastating April 1906 Earthquake and Fire. These volumes were in fact damaged by the fire but remain largely intact with some content loss in some of the volumes. The atlases are the property of the San Francisco Public Library. Original 1899 survey is overlaid with pasted-in building updates for ten different dates, the last being September 1905. Maps in full color with detailed legend including firehouses, stables, elevators, chimneys, steam boilers, firewalls, doorways, etc.
Take a look at the maps here, and while there, browse around the other great maps Mr. Rumsey has put up.