You can see by the ladder against the scaffold just how big the mountain really was, you can also the the left and right side backdrops do not continue any further than they had to. No Polaroid pictures here, private cameras were forbidden on the backlot or sets, so one had to be a bit sneaky to get any pics. The famous cable car sequence was one of the best parts in the movie, only problem the castle "SCHLOSS ADLER" (Hohenwerfen) they filmed on location in Austria didn't have a cable car which was an integral part of the story so a model mountain the height of 2.5 double decker buses was built on the backlot. Even close up it looked real. As I said cameras were forbidden in the studio so I smuggled in a Kodak instamatic disguised as my lunch and removed the paper bag from around the lens and viewfinder and sneaked up the lot in my lunch hour and I am glad I did the mountain was destroyed a week after these pics were taken.