March 2012
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Slate article saves cartographer!

If you might recall, I posted a “must read” article about a great cartographic map.

Well – there is a nice back-story now (thanks Kayla Folkins from Pasadena for passing this along) about how all of the posting saved this person’s business!

Still lots of interest in maps, I guess!

Creating a network dataset in ArcMap from Free data

Link to the code

I wanted to pass this along and send a thank you to Kristen.  I would love for  someone to create a network dataset for all of LA County – it would be a valuable resource:

Hey Mark,

I did some researching and found a way where I could acquire roadway data and assemble it into a network dataset for route analysis in ArcMap.

The process mainly involved downloading the Open Street Map data and using the program, “Open Street Map to Network Dataset” (OSM2NDS). Users of OSM’s website are limited in how many nodes that can download from the OSM website at a time. As a work around, I downloaded segments of the entire geography I was interested in, converted the OSM files to network datasets, and then appended the source files of the network datasets into a larger files and rebuilt the network dataset using the specifications of the network datasets created by OSM2NDS.

You can download OSM2NDS at this location:

And the OSM to Network Dataset conversion program is open source.

If you haven’t caught wind of this, feel free to pass this along to your colleagues.




We found the Sanborn Map collection!

I recently was able to see a map of my neighborhood and house (which was built in 1928) as it appeared in 1929!  The maps were created during the middle of the development of my neighborhood, so about 2/3 of the current houses are missing.  It’s interesting to see.  If your city manager or department head, or your friend, needs to see the way things were as their cities or neighborhoods developed, this is a valuable resource!

How did I see those?  At the recent SoCalGIS meeting held at CSUN, we were given a tour of the map library, which turns out to have a repository of Sanborn Fire Insurance maps for the Western US dating back to the 1800′s!   What is a Sanborn map?

The Sanborn Maps were originally created for assessing fire insurance liability in urbanized areas in the United States. The maps include detailed information regarding town and building information in approximately 12,000 U.S. towns and cities from 1867 to 2007. Author Kim Keister describes the legacy of Sanborn maps: “Stated simply, the Sanborn maps survive as a guide to American urbanization that is unrivaled by other cartography and, for that matter, by few documentary resources of any kind.”[1]They are a highly useful resource for historical research, planning, preservation, genealogical research, sociological studies and research of urban geography.

For details:

So I immediately asked for the flat maps of my neighborhood (Montrose, CA) and started to enjoy going back in time.

Check out the high resolution version of the commercial area: Full resolution (zipped .jpg file)


Free Webinar: Getting Rolling with HTML5 and ESRI technology

I wanted to pass along this free webinar from Latitude Geographics – they are moving toward the HTML5 standard for web and mobile apps – which is great for us.  I recommend folks to check this out:

Link to sign up

USGS most fascinating Topo Map

A bit of tongue in cheek humor – I wish all the maps we made could be like this ;) (but then we wouldn’t have jobs).