Perry-Castañeda Library-southern europe 1943 maps: How to georeference?

The Perry-Castañeda Library Map Collection, located at the University of Texas, is one of the largest digital map collections in the world. This collection contains maps of all continents and many countries, as well as topographic, nautical, geological, and historical maps. In particular, the 1943 topographic maps for Southern Europe are of great value to geographers, historians and map enthusiasts.

The 1943 topographic maps for Southern Europe were produced by the U.S. Army during World War II. These maps were created to assist American troops in their military operations in Southern Europe. The maps were produced at a scale of 1:25,000 and cover much of Italy, France, Spain and Portugal.

These 1943 topographic maps are of great historical importance, as they show the landscapes, cities and roads of Southern Europe at the time of World War II. The maps can be used to understand the military history of this period and to see how battles were fought and won.

In addition, these topographic maps are also very useful for researchers and students of geography, cartography and urban planning. The maps can be used to study the evolution of the landscape and urbanization, as well as to compare cities and landscapes today with those of decades ago. The maps can also be used to plan hiking or travel routes, as they provide detailed information about roads, mountains, rivers, and forests.

The Perry-Castañeda Library Map Collection has digitized these 1943 topographic maps to make them easily accessible to researchers and students worldwide. The maps are available online and can be viewed for free. Users can search for specific maps using the advanced search tools, or browse the collection by region, country, or theme.

In conclusion, the 1943 topographic maps for Southern European countries are a valuable resource for researchers, students, and map enthusiasts. Through the Perry-Castañeda Library Map Collection, these maps are easily accessible and can be used to understand history, study the landscape, and plan travel. If you are interested in military history, geography, or cartography, I encourage you to explore this fascinating collection.

Georeferencing a scanned map

Nothing could be simpler than finding 4 points at the four corners of the map to enter set points. The set points correspond to a precise position on the raster to which we associate a pair of XY coordinates in the reference coordinate system.

Forget about Latitudes/Longitudes because they position a point on a sphere and not on a plane, and our map is indeed a plane. In this example, the coordinates are the numbers in red. The intersection of the grid in the corner corresponds to the coordinates 280000 meters East and 466000 meters North.

But you need to know in which coordinate system the map was made. It is found in the title block of the map:

We are not going to do here the georeferencing tutorial in QGis. It is very well described in the official documentation:

On the other hand, you should know that all that QGis will ask you to do in order to enter the set points and to georeference the map definitively, is the coordinate system to use. It can offer you hundreds of systems that it has in memory, but, unfortunately, the maps are from 1943 and the systems used at that time are almost all forgotten. We’ll fix that here.

What are the 1943 coordinates systems?

Here is the map that tells you which system to use, depending on the location of the map. The only one present in the QGis list is the French Lambert Zone 3, but don’t be mistaken because it offers a dozen of them!

If not, as for the Iberian Peninsula Zone, South Italy Zone and North Italy zone, they are not listed. We will add them.

Adding new SCRs

Go to the menu Preferences -> Custom Projections…

Click on the + button.

Projection Iberica Peninsula Zone

Enter the name you want to see in the list of available projections. For example “Maps 1943 P. Iberica” for the Iberica Peninsula Zone.

Then copy and paste the following text into the Settings window:

PROJCRS["Iberic_peninsula_zone",  BASEGEOGCRS["GCS_Datum_Lisboa_Hayford",DATUM["D_Datum_Lisboa_Hayford", ELLIPSOID["International 1924",6378388,297,  LENGTHUNIT["metre",1],  ID["EPSG",7022]]],PRIMEM["Greenwich",0, ANGLEUNIT["Degree",0.0174532925199433]]],  CONVERSION["unnamed",METHOD["Lambert Conic Conformal (2SP)", ID["EPSG",9802]],PARAMETER["Latitude of false origin",40, ANGLEUNIT["Degree",0.0174532925199433], ID["EPSG",8821]],PARAMETER["Longitude of false origin",-3.68737499, ANGLEUNIT["Degree",0.0174532925199433], ID["EPSG",8822]],PARAMETER["Latitude of 1st standard parallel",40, ANGLEUNIT["Degree",0.0174532925199433], ID["EPSG",8823]],PARAMETER["Latitude of 2nd standard parallel",40, ANGLEUNIT["Degree",0.0174532925199433], ID["EPSG",8824]],PARAMETER["Easting at false origin",600000, LENGTHUNIT["metre",1], ID["EPSG",8826]],PARAMETER["Northing at false origin",530000, LENGTHUNIT["metre",1], ID["EPSG",8827]]],  CS[Cartesian,2],AXIS["(E)",east, ORDER[1], LENGTHUNIT["metre",1,  ID["EPSG",9001]]],AXIS["(N)",north, ORDER[2], LENGTHUNIT["metre",1,  ID["EPSG",9001]]]]

This text corresponds to the definition of SCR in WKT2. Click on Validate to make sure the copy is correct and click on OK.

Now, when you open the SCR definition window for a layer, you have the 1943 system on the list:

Projection South Italy

WPT2 code is :

PROJCRS["Lambert_Conformal_Conic",BASEGEOGCRS["Bessel 1841",DATUM["Not specified (based on Bessel 1841 ellipsoid)",ELLIPSOID["Bessel 1841",6377397.155,299.1528128,LENGTHUNIT["metre",1]],ID["EPSG",6004]],PRIMEM["Greenwich",0,ANGLEUNIT["Degree",0.0174532925199433]]],CONVERSION["unnamed",METHOD["Lambert Conic Conformal (1SP)",ID["EPSG",9801]],PARAMETER["Latitude of natural origin",39.5,ANGLEUNIT["Degree",0.0174532925199433],ID["EPSG",8801]],PARAMETER["Longitude of natural origin",14,ANGLEUNIT["Degree",0.0174532925199433],ID["EPSG",8802]],PARAMETER["Scale factor at natural origin",0.9989,SCALEUNIT["unity",1],ID["EPSG",8805]],PARAMETER["False easting",700000,LENGTHUNIT["metre",1],ID["EPSG",8806]],PARAMETER["False northing",600000,LENGTHUNIT["metre",1],ID["EPSG",8807]]],CS[Cartesian,2],AXIS["easting",east,ORDER[1],LENGTHUNIT["metre",1,ID["EPSG",9001]]],AXIS["northing",north,ORDER[2],LENGTHUNIT["metre",1,ID["EPSG",9001]]]]

Projection North Italy

The WPT2 code is:
PROJCRS[“Lambert_Conformal_Conic”,BASEGEOGCRS[“Bessel 1841”,DATUM[“Not specified (based on Bessel 1841 ellipsoid)”,ELLIPSOID[“Bessel 1841”,6377397.155,299.1528128,LENGTHUNIT[“metre”,1]],ID[“EPSG”,6004]],PRIMEM[“Greenwich”,0,ANGLEUNIT[“Degree”,0.0174532925199433]]],CONVERSION[“unnamed”,METHOD[“Lambert Conic Conformal (1SP)”,ID[“EPSG”,9801]],PARAMETER[“Latitude of natural origin”,45.9,ANGLEUNIT[“Degree”,0.0174532925199433],ID[“EPSG”,8801]],PARAMETER[“Longitude of natural origin”,14,ANGLEUNIT[“Degree”,0.0174532925199433],ID[“EPSG”,8802]],PARAMETER[“Scale factor at natural origin”,0.9989,SCALEUNIT[“unity”,1],ID[“EPSG”,8805]],PARAMETER[“False easting”,800000,LENGTHUNIT[“metre”,1],ID[“EPSG”,8806]],PARAMETER[“False northing”,601000,LENGTHUNIT[“metre”,1],ID[“EPSG”,8807]]],CS[Cartesian,2],AXIS[“easting”,east,ORDER[1],LENGTHUNIT[“metre”,1,ID[“EPSG”,9001]]],AXIS[“northing”,north,ORDER[2],LENGTHUNIT[“metre”,1,ID[“EPSG”,9001]]]]

Lambert Zone 3 projection

Lambert III’s are abundantly available on the list of available SCR’s. The one that corresponds to the one used in 1943 is the

NTF (Paris)/Sud France EPSG:27593

With all the others, you’ll be in the middle of Africa with a bit of luck!

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