Heidi (2005 live-action film) - Wikipedia

1hr 44mins
Dir: Paul Marcus
Starring: Max von Sydow and Emma Bolger

A young orphan girl goes to stay with her morose grandfather in the Swiss Alps

This film is one of a number produced over the years that have been based on the iconic 1881 Swiss novel Heidi by Johanna Spyri, and this version should not to be confused with the animated film of the same name that was released in the same year. This production of the classic tale features some brief scenes that were shot on the Gwili Railway at Bronwydd Arms station which appears as ‘Mayenfeld’. However, not is all as it seems. The actual train is Slovenian, with some very fine shots of SZ 2-6-2T No.17-006. These Slovenian Railway scenes were then slotted into the shots of the station at Bronwydd Arms where there are close up views of Mk.1 coaching stock but little else.

This is about as good as the UK railway scenes get. Bronwydd Arms station on the Gwili Railway. The production crew have done a fine job in fooling the viewer in to believing that this is Switzerland because, quite frankly, this could be anywhere.