My comments are based on two things: First that Austrian railroad
officials (and, I think the engineer I had the cab ride with) said
that parts of the movie were filmed there; and second, from personal
observation, there are locations on this line that look exactly
like the scenes in the movie.

Parts of the moview may have been shot in Spain, but there are very
different looks to the railroad infrastructure in different countries.
Spain may well be closer to looking like Italy.

Based on what I have read and heard from various people, parts of
movies are often shot in different parts of the world -- while
the scenes supposedly portray locations near each other.

-- Ernest