Old Insurance Maps – Georeferencing Sanborn Fire Insurance Maps on Modern Maps

I developed and maintain this site so I am both very happy to see it get posted here and also watching htop intently...

I wanted to point out it is a crowdsourcing project, so every overlaid page you see has been placed there by a person, often through large institutional efforts at universities, but also individuals just looking to learn about their hometown through these old maps. Thanks for the interest!

Sanborn Fire Insurance maps document cities in extreme detail. Not only are the positions and shapes of buildings accurately mapped, but also rough outlines of the rooms, their construction materials, and even small details like if the building hired a night watchman. See downtown San Fracisco for example: https://oldinsurancemaps.net/viewer/san-francisco-ca/?sanbor...

Thanks for sharing. I went through a similar process recently, manually stitching together fire insurance maps from my hometown. A large part of the business district burned down in 1916, but maps from a couple of years earlier survived. It worked, but it was tedious. This would have saved a lot of time. Here's the link if anyone wants to check it out: https://fire.gorch.com/

Clicking on a lot of the maps gives me this ? I'm logged in as well

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