function of border: to wall in

The issue of borders keep my mind busy, although it's already long time I live in Europe without borders and I still ask if Europe is really without borders?
If we look back, at the time when a border was a synonym to a wall in Europe..
And we can easily do that nowadays, 20 years past. The German National media - Deutsche Welle, has developed a unique project presenting the animated depiction of the former German-German border. Click on the picture to open the video.