In this sequence, Joongi is running around in Chur. This would strike you as funny, if you knew that town. It's very nice, don't get me wrong ... but it's also very tiny. 34'000 inhabitants. He is mainly running around in front on Manor (see the half-covered sign in the background), which is one of the department stores in Switzerland (previously called Vilan). No chaebol family or hot (but dysfunctional) chaebol heir attached to it, unfortunately. In later parts of the clip, he is running up Poststrasse. I looked out for my mother or father-in-law, but sadly, they didn't make an appearance in the background.
the hotel he stayed at (ABC Hotel).
The shooting, however, took place in Zuoz, as you all know by now. There's the red house (wrote about that enough, I think) - and there is a yellowish house, which is on the town square. It looks far more yellow in this shot than in the movie. They probably photoshopped this one:
Pfistern in Lucerne. How do I know? Cause it says so in the background. Ouf. Saved. I wouldn't have had a clue otherwise. It's their "Weihnachtswald" (= Christmas forest) setting. Where you sit outside. Great way to freeze to death immediately! And you won't even notice the pain of the Fondue in your stomach.
And here's the video!