Before I begin: PLEASE NOTE: I am also looking for paid summer internships that have a map making component. I can send my resume and anything else if you are interested. Tweet, email, you know the drill…
A little more info. These are based off the map from 1839 by David H. Burr from
“The American atlas, exhibiting the post offices, post roads, rail roads, canals, and the physical & political divisions of the United States of North America” found on the Library of Congress’ website. As I may have already discussed in a previous post, David H. Burr was the official topographer for the U.S. House of Representatives. Because of this, I presume that the atlas was probably the standard and the authority for the transportation networks of the United States at that time. Unlike my previous post road map, where I easily georectified one map on top of the map of the modern U.S.,this was much more complicated. Being an atlas, this map was in multiple pages. I was forced to first crop each page on photoshop so there would be no extraneous parts. Then, starting with New England, I not only georectified the 1839 map to the modern United States, but also to its neighboring 1839 state maps. Because many of the post roads were connected between states, I needed to ensure that they matched up to one another, not just the modern day map.
Though this shapefile isn’t as accurate as with the other post road map, it is interesting to compare the map from 1851 to 1839 and see the development of the transportation networks in the United States. Again, on this map, you see the spider web-like patterns, where a large city is the center of the web, with many different roads expelling from it.
In order to upload this files to ArcGIS online and to fully see the shapefile, I had to dissolve the lines into one large polyline. You have the option to either download the dissolved or undissolved shapefile and also to view the dissolved or undissolved feature layer.
Dissolved Shapefile – http://bit.ly/1J9Lz0a
Undissolved Shapefile – http://bit.ly/1J9MrSg
1839 David H. Burr Post Roads by Laura Newman Eckstein is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Based on a work at http://lauraneckstein.com/blog/1839postroads/.