One benefit of using a Geographic Information System (GIS) computer mapping software is the ability to overlay historic paper maps on contemporary aerial imagery. The HPOWEB mapping website now provides users the opportunity to view over a dozen maps published between 1865 and 1929 in this manner.
The first step to viewing historic paper maps “at their real-world location” is to scan, or digitize, the drawing. Next, the resulting digital image must be pinned to coordinates at the location it represents – a process called georeferencing. In this way, the GIS software will know, for example, that a map of Surry County should “show up” not in the Atlantic Ocean, but rather in northwestern North Carolina.
The good folks at the University of North Carolina at Chapel Hill have georeferenced over 150 historic maps – a collection that includes county soil surveys, highway maps, town plans, and an 1884 map depicting the “former territorial limits of the Cherokee Nation of Indians”. Each map contains a plethora of details of great interest to historians, archaeologists, and arm-chair culturalists.
You can view these georeferenced maps at their website: http://www2.lib.unc.edu/reference/gis/historical/ncmaps.html
The Historic Preservation Office GIS staff have incorporated 14 of these maps into HPOWEB so that users can not only see the historic map in relation to contemporary aerial imagery, but also in relation to historic resources that have been previously surveyed and mapped by the office.
These maps are viewable only within the Advanced User version of HPOWEB, accessible from: http://gis.ncdcr.gov/hpoweb/default.htm?config=AdvancedUser.xml
From the toolbar, click on the Advanced Tools icon (it looks like a toolbox with a white plus sign), and then on the first option, Map Services.
In the Enter Keyword text box, type historic, and then click the Find Data button.
The first match in the list of choices at the bottom of the dialog box is NC Historic Maps.
Hover over the name and, once the yellow highlight appears, click the Load Service button.
The scanned, georeferenced historic paper maps will display in HPOWEB across the state. At this point, you can minimize or close the Map Services dialog box.
The service is listed as a new layer at the top of the HPO Data Layers content list. Note that you can see which historic maps we have displayed by clicking on the small grey arrow to the left of the layer name.
Zoom into the southern portion of the Surry County map, published in 1921 by the North Carolina Geological and Economic Survey. The map displays schools, houses, churches, installed and suggested water transmission lines, and developed and undeveloped dam sites.
Next, zoom in further to see the Little Richmond School.
Since the NC Historic Maps layer is at the top of the HPO Data Layers content list, it obscures the other HPO map data listed below it. Move the NC Historic Maps layer down the list by clicking on the small grey arrow to the right the layer name, and then clicking the option to Move down.
After doing this once, the HPO Data points will appear on top of the historic map (the boundary shading is still below the historic map). Note that there is a surveyed point for the c. 1920 Little Richmond School, though it is no longer extant, having been moved or demolished sometime before 1993.
Just to the east of the Little Richmond School is another school labeled Col. on the Surry County map. Might this be a Rosenwald School? While no school currently exists at this spot, either, knowing the location of this second school could provide very useful to a historian researching the education of African-American students of Surry County.
We hope users find this new addition of old maps helpful. Let us know if you would like us to add another of UNC’s collection of georeferenced maps to HPOWEB – or perhaps a digitized map from your own collection!
Contact GIS staffers Andrew Edmonds (firstname.lastname@example.org) or Michael Southern (email@example.com) to learn more.