Walking Across European Borders (WW2): Portugal to Liechtenstein
During WW2, there were only two options to walk through every mainland European country (except 3) once: from Portugal to Liechtenstein, and its reverse.
Omitted continental countries: Monaco, San Marino, Vatican City
With the help of a map, can you guess all modern day countries that were at one point controlled by the Axis powers and their co-belligerents during World War II?