OldInsuranceMaps
@oldinsurancemaps.net
A public space for georeferencing (and exploring) historical fire insurance atlases ~ https://oldinsurancemaps.net ~ app development on GitHub: https://github.com/ohmg-dev/OldInsuranceMaps
🔓🚀
Just made my first edit ever to @openhistoricalmap.org using @oldinsurancemaps.net backgrounds. Feels like I just unlocked something big. Immediately requested more maps. Now I have to bring this to the attention of the local historical societies
February 5, 2026 at 12:42 AM
🔓🚀
Reposted by OldInsuranceMaps
Riverside and San Bernardino, California are now on @oldinsurancemaps.net!
oldinsurancemaps.net/viewer/river...
oldinsurancemaps.net/viewer/san-b...
Will hopefully be processing more maps this month
oldinsurancemaps.net/viewer/river...
oldinsurancemaps.net/viewer/san-b...
Will hopefully be processing more maps this month
Riverside, Calif.
oldinsurancemaps.net
February 2, 2026 at 11:22 PM
Riverside and San Bernardino, California are now on @oldinsurancemaps.net!
oldinsurancemaps.net/viewer/river...
oldinsurancemaps.net/viewer/san-b...
Will hopefully be processing more maps this month
oldinsurancemaps.net/viewer/river...
oldinsurancemaps.net/viewer/san-b...
Will hopefully be processing more maps this month
Upcoming: Mapping USA and Code4Lib: https://blog.oldinsurancemaps.net/2026/01/27/upcoming-mapping-usa-and-codelib/
January 27, 2026 at 6:18 PM
Upcoming: Mapping USA and Code4Lib: https://blog.oldinsurancemaps.net/2026/01/27/upcoming-mapping-usa-and-codelib/
Reposted by OldInsuranceMaps
Sanborn to Run: Overcoming Workplace Obstacles for Fire Insurance Surveyors
"surveyors did not exactly get the red carpet rolled out for them...sometimes they were locked out on high-rise roofs, attacked by dogs, shot at by smugglers, and even seized by military police on suspicion of espionage."
"surveyors did not exactly get the red carpet rolled out for them...sometimes they were locked out on high-rise roofs, attacked by dogs, shot at by smugglers, and even seized by military police on suspicion of espionage."
Sanborn to Run: Overcoming Workplace Obstacles for Fire Insurance Surveyors | Worlds Revealed
Sanborn Map Company fire insurance surveyors successfully mapped many thousands of cities and towns across North America, but they were often viewed with suspicion by locals and they were not granted ...
blogs.loc.gov
January 25, 2026 at 1:05 PM
Sanborn to Run: Overcoming Workplace Obstacles for Fire Insurance Surveyors
"surveyors did not exactly get the red carpet rolled out for them...sometimes they were locked out on high-rise roofs, attacked by dogs, shot at by smugglers, and even seized by military police on suspicion of espionage."
"surveyors did not exactly get the red carpet rolled out for them...sometimes they were locked out on high-rise roofs, attacked by dogs, shot at by smugglers, and even seized by military police on suspicion of espionage."
Come join us online at Mapping USA (Jan 31st) in a workshop with OpenHistoricalMap @openhistoricalmap.org and Yesterdays yesterdays.maprva.org! We'll be demonstrating and discussing how all three of these community historical projects can be integrated openstreetmap.us/events/mappi...
Historical Mapping with OpenHistoricalMap, OldInsuranceMaps.net, and Yesterdays
From georeferencing historical Sanborn fire insurance maps on OldInsuranceMaps.net, to georeferencing historical photographs, to mapping through time on OpenHistoricalMap, we’ll share demos and how to...
openstreetmap.us
January 15, 2026 at 2:35 PM
Come join us online at Mapping USA (Jan 31st) in a workshop with OpenHistoricalMap @openhistoricalmap.org and Yesterdays yesterdays.maprva.org! We'll be demonstrating and discussing how all three of these community historical projects can be integrated openstreetmap.us/events/mappi...
So happy to support projects like Yesterdays! That's exactly what OIM is all about :)
OldinsuranceMaps.net is such an amazing and thoughtful tool. So easy to georeference these maps and look back in time. Do yourself a favor and go poke around.
@maprva.org's Yesterdays project would have been impossible without it. yesterdays.maprva.org
@maprva.org's Yesterdays project would have been impossible without it. yesterdays.maprva.org
December 6, 2025 at 11:56 PM
So happy to support projects like Yesterdays! That's exactly what OIM is all about :)
A recent addition to the multimask tool: color-coded vertices based on snapping. Sat down a week ago to write a little blog post about it, and decided to turn it into a whole (re)introduction to that tool: blog.oldinsurancemaps.net/post/2025-12...
Blog | OldInsuranceMaps.net
The multimask is a concept in OldInsuranceMaps.net that greatly eases the creation of seamless mosaics from many different...
blog.oldinsurancemaps.net
December 2, 2025 at 2:10 PM
A recent addition to the multimask tool: color-coded vertices based on snapping. Sat down a week ago to write a little blog post about it, and decided to turn it into a whole (re)introduction to that tool: blog.oldinsurancemaps.net/post/2025-12...
Reposted by OldInsuranceMaps
Took the bus today, stopped in at my favorite boutique oil refinery
November 14, 2025 at 2:15 PM
Took the bus today, stopped in at my favorite boutique oil refinery
Reposted by OldInsuranceMaps
join us yesterdays.maprva.org
November 12, 2025 at 6:54 PM
join us yesterdays.maprva.org
Reposted by OldInsuranceMaps
Super easy to use the mapgl package and @oldinsurancemaps.net to compare 1886 Richmond, VA to today in #rstats. The site of Gallego Mills, the ruins of which became an iconic photo after the fall of Richmond in the American Civil War, is now an office building and freeway.
October 9, 2025 at 4:14 PM
Super easy to use the mapgl package and @oldinsurancemaps.net to compare 1886 Richmond, VA to today in #rstats. The site of Gallego Mills, the ruins of which became an iconic photo after the fall of Richmond in the American Civil War, is now an office building and freeway.
From some recent activity, here's a rare but good example (from Worcester Mass.) of where the Thin Plate Spline transformation makes sense for #georeferencing #sanborn maps. Curved roads out in space are sometimes drawn without good scale and need extra distortion oldinsurancemaps.net/layer/72727
October 6, 2025 at 7:38 PM
From some recent activity, here's a rare but good example (from Worcester Mass.) of where the Thin Plate Spline transformation makes sense for #georeferencing #sanborn maps. Curved roads out in space are sometimes drawn without good scale and need extra distortion oldinsurancemaps.net/layer/72727
Often people ask about adding historical photos to OIM (not a planned feature!) so it's awesome to see our maps used in other apps that are made to do just that 😍
What a fantastic first week of our Georeference Tool! We already have over 500 image georeferences across Richmond, and we're working on importing new datasets!
Our map viewer now allows you to sort by date, and overlay Sanborn insurance maps from the 1900s.
Check it out: georeference.maprva.org
Our map viewer now allows you to sort by date, and overlay Sanborn insurance maps from the 1900s.
Check it out: georeference.maprva.org
September 18, 2025 at 9:47 PM
Often people ask about adding historical photos to OIM (not a planned feature!) so it's awesome to see our maps used in other apps that are made to do just that 😍
So cool to see new research enabled by existing crowdsourced work on OldInsuranceMaps!
I just found out about this from @resourcefulsqrl.bsky.social and I cannot properly convey my excitement because one of the map sets I need for my book are georeferenced and ready to go and that makes it so much easier as a postdoc who doesn’t have protected research time to make figures.
If you are in the New Orleans area, come to one of our upcoming Georeference-a-thons at Second Line Brewing! Tuesday evenings, the 16th and 23rd. RSVP form here: tiny.cc/georef-2025. We'll be focusing on 1895 Duncan Plaza area and hearing from archaeologists who did work there over the summer.
September 15, 2025 at 6:18 PM
So cool to see new research enabled by existing crowdsourced work on OldInsuranceMaps!
Next week! And the one after. These two-week-in-a-row event are really great for getting a bit more reach.
If you are in the New Orleans area, come to one of our upcoming Georeference-a-thons at Second Line Brewing! Tuesday evenings, the 16th and 23rd. RSVP form here: tiny.cc/georef-2025. We'll be focusing on 1895 Duncan Plaza area and hearing from archaeologists who did work there over the summer.
September 12, 2025 at 8:47 PM
Next week! And the one after. These two-week-in-a-row event are really great for getting a bit more reach.
New blog post about how OldInsuranceMaps.net uses #gdal fantastic virtual raster format during the georeferencing process. blog.oldinsurancemaps.net/post/2025-08..., also has a link to a recording of my recent I-GUIDE presentation: "A look inside OldInsuranceMaps.net"
OldInsuranceMaps.net
A crowdsourcing site for creating and viewing georeferenced mosaics of historical Sanborn fire insurance maps
OldInsuranceMaps.net
August 9, 2025 at 3:00 PM
New blog post about how OldInsuranceMaps.net uses #gdal fantastic virtual raster format during the georeferencing process. blog.oldinsurancemaps.net/post/2025-08..., also has a link to a recording of my recent I-GUIDE presentation: "A look inside OldInsuranceMaps.net"
This past spring the Community Mapping Lab at University of Georgia used OldInsuranceMaps to host a mapathon, where a large group got together and georeferenced Sanborn maps together. Looks like fun! See their work here: oldinsurancemaps.net/map/sanborn0... #crowdsourcing #sanborn #historicalmaps
July 25, 2025 at 3:35 PM
This past spring the Community Mapping Lab at University of Georgia used OldInsuranceMaps to host a mapathon, where a large group got together and georeferenced Sanborn maps together. Looks like fun! See their work here: oldinsurancemaps.net/map/sanborn0... #crowdsourcing #sanborn #historicalmaps
Come learn about OldInsuranceMaps.net at the I-GUIDE Virtual Consulting Office presentation on Wednesday morning! Really looking forward to doing a more technical talk than I have before: i-guide.io/i-guide-vco/...
A look inside OldInsuranceMaps.net, a crowdsourcing platform for georeferencing historical fire insurance maps : I-GUIDE
i-guide.io
July 14, 2025 at 11:06 PM
Come learn about OldInsuranceMaps.net at the I-GUIDE Virtual Consulting Office presentation on Wednesday morning! Really looking forward to doing a more technical talk than I have before: i-guide.io/i-guide-vco/...
Big day: Asset storage backend migrated to S3 object storage (wasabi)! github.com/ohmg-dev/Old.... Newsletter coming "soon".
Implement S3 storage compatibility by mradamcox · Pull Request #280 · ohmg-dev/OldInsuranceMaps
Updates the code base to be fully compatible with using an S3 object store-based storage backend, to address #275. Uses storages.backends.s3boto3.S3Boto3Storage from django-storages (v1.13.x for no...
github.com
June 22, 2025 at 11:12 PM
Big day: Asset storage backend migrated to S3 object storage (wasabi)! github.com/ohmg-dev/Old.... Newsletter coming "soon".
Reposted by OldInsuranceMaps
this is much, much easier than what i was planning to do. thank you! dare i say therapeutic even.
June 15, 2025 at 1:03 AM
this is much, much easier than what i was planning to do. thank you! dare i say therapeutic even.
Reposted by OldInsuranceMaps
YO 🌯⚖️
@ktflghm.bsky.social - I'd say @openhistoricalmap.org is the closest thing to Pastmapper these days & I even made fun of how little progress has been made since PM's glory days in a slide a few years ago... @mradamcox.bsky.social's oldinsurancemaps.net is my go-to for Sanborn mosaics.
@ktflghm.bsky.social - I'd say @openhistoricalmap.org is the closest thing to Pastmapper these days & I even made fun of how little progress has been made since PM's glory days in a slide a few years ago... @mradamcox.bsky.social's oldinsurancemaps.net is my go-to for Sanborn mosaics.
June 13, 2025 at 9:05 PM
YO 🌯⚖️
@ktflghm.bsky.social - I'd say @openhistoricalmap.org is the closest thing to Pastmapper these days & I even made fun of how little progress has been made since PM's glory days in a slide a few years ago... @mradamcox.bsky.social's oldinsurancemaps.net is my go-to for Sanborn mosaics.
@ktflghm.bsky.social - I'd say @openhistoricalmap.org is the closest thing to Pastmapper these days & I even made fun of how little progress has been made since PM's glory days in a slide a few years ago... @mradamcox.bsky.social's oldinsurancemaps.net is my go-to for Sanborn mosaics.