Achim Rumberger shows how to map German postal codes using R:
Just at this time Ari published his webinar about getting shape files into R. Which also includes a introduction to shape files to get you going, if you are new to it, as I am. I remembered Ari from his mail course introducing his great R-package (choroplethr). By the way this is a terrible name, being a biologist by heart, I always type “chloroplethr”, as in “chlorophyll”, and this is not found by the R package manager. [Editor’s note: I agree!]
Next question, where do I get the shapefiles, describing Germany? A major search engine was of great help here. http://www.suche-postleitzahl.org/downloads?download=zuordnung_plz_ort.csv . Germany has some 8700 zip code areas, so expect some time for rendering the file, if you do on your computer. Right on this side one can also find a dataset which might act as a useful warm up practice to display statistical data in a geographical context. Other sources are https://datahub.io/de/dataset/postal-codes-de
This is really cool.