Upcoming: Mapping USA and Code4Lib: https://blog.oldinsurancemaps.net/2026/01/27/upcoming-mapping-usa-and-codelib/

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."

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 :)

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...

Took the bus today, stopped in at my favorite boutique oil refinery

join us yesterdays.maprva.org

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

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!

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"

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/...

Big day: Asset storage backend migrated to S3 object storage (wasabi)! github.com/ohmg-dev/Old.... Newsletter coming "soon".

this is much, much easier than what i was planning to do. thank you! dare i say therapeutic even.

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.