I first became aware of the Wuppertal suspended train system when I saw it in an episode of the 70s ITC thriller series The Adventurer (though the series was hardly thrilling or particularly adventurous!). If I recall correctly, the episode was called I'll Get There Sometime, if anyone fancies seeking it out.
Good memory there, Alan. I vaguely remember the series and I do have the theme tune somewhere among my old LP's. Could be the one with John Barry themes but I wouldn't swear on it. I laugh when I read that a particular show only had one series - then you realise as in this case that one series meant twenty six episodes.
I had a quick look at the writing credits and there's something familiar about the names. Quite a few similarities between this show and Randall and Hopkirk Deceased.