Lee Jun-ki in Switzerland ... Video & Details

Hello, everyone! Ah, how I miss the days when I was still real-time stalking ...
I am so glad there is video footage at least, because a) it proves Joongi was really here and b) I can do some more location-identification. I've missed it!

Here's the video with English subs on JG Family's Facebook page:

You see Joongi in the Rhätische Bahn (Rhaetian Railway), which is a train company that (almost) only runs in Switzerland’s trilingual canton of Graubünden, since 1888. Their network contains 84 tunnels and some pretty spectacular viaducts. It has a unique track-width, which is called "metre gauge" (cause it's exactly 1 meter or 3 ft 3 3⁄8 in wide). Normal Swiss trains can't use these tracks. Yeah, we Swiss are train fanatics! All of us!
The famous Landwasser Viaduct

He is travelling 1st class and is alone in the carriage - I assume he either rented to whole train and at least the wagon (indication for the first: usually, the trains are far longer). So, which line is he on (there is nine: Landquart–Davos line; Davos–Filisur line; Landquart–Thusis line; Albula line; Reichenau–Disentis/Mustér line; Engadin line; Bernina line; Arosa line; Bellinzona–Mesocco line; Vereina line)?

I know for sure it's not the last three (cause I know what they look like) - and if you pay close attention, you see a station sign whizz by at 0:57. I am not 100% certain, but I think it's Bergün/Bravuogn - which makes this this Albula line. They obviously cut such an interview together, so the background is not continuous - he seems to have stayed in the same train the whole time, however. 
Bergün in the summer
The lake at the very beginning (at 0:02) is Lake Silvaplana, to the left, a bit elevated, you see a wonderful (and very expensive) hotel, the Hotel Waldhaus Sils-Maria. Sils is probably the most beautiful spot on earth. I would totally go live there if I could.

At 1:16, we see the Piz Corvatsch (as identified here already) - and thanks to the video, we now also know what the crew was sitting on! Some type of viewing platform. Also: it seems the helicopter wasn't used for flying around but for filming from above (and probably for bringing up equipment to Corvatsch). Joongi used the cable care, like "normal people". Good on you, Joongi! Sorry to hear about the altitude sickness!

1:52 to 1:54: that's a shot of the Engadin line; 2:50 onwards is shot in Zuoz. Here is the red house, where is is shooting in front of:
At 4:02, there is a writing on the house: "Entra co cun buna gluna sorta eir cun quell adüna". This is Rumantsch, Switzerland's fourth language! It says (roughly): "You should enter here with a good mood and should exit with one!"

Thanks, yes! I'm in a very good mood now - see you soon, Joongi!