My wife and I were greeted at the bus door by a smiling Maria-lookalike complete with green dirndl, today's version of the traditional Germanic dress now most commonly seen at Oktoberfests. This Maria was in fact named Sharron and turned out to be an Israeli-born, English-raised Austrian. Most importantly, she was a Sound of Music devotee with a sense of humour. This became clear as she asked for the nationalities of the 50-odd people onboard, asking the sole German who raised his hand, "what are you doing here?!"

I was aware Germans had never embraced the 20th Century Fox movie, despite it being the first US film to have both the dialogue and music fully dubbed. An exchange semester during university had shown me the sad state of ignorance of Julie Andrews among many Germans (they could all speak three languages, but I doubt that compensates.) And I could understand why a German distributor of the movie chose to cut the whole third and final act, removing the swastikas and references to the Nazis, before being overruled by Fox.

But as Sharron explained, modern-day Austrians themselves were none the wiser about the movie, despite its setting and description of an Austrian defiance of the Third Reich annexation. Annoyed by the use of non-traditional costumes and replacement of Austrian folk songs with the Rodgers and Hammerstein numbers, the film had apparently never gotten out of the shadow of the two Die-Trapp Familie movies made in the 1950s which remain popular in German-speaking countries.

The bus trip covered all the city's movie sites, from the property used for the driveway entrance and facade of the von Trapp villa at the end of Maria's I Have Confidence song and run, to the separate palace and lake where the exuberant children and their new governess fall in, to the embarrassment of their father.

Sharron explains or reminds people of the plot at various points, describing the factors Maria considers when choosing between full-time life at the church and the Captain.

"I really want to be a nun, but he's hot," she says.

A stop at a park reveals the gazebo, scene of Liesl's Sixteen Going on Seventeen and post-song smooch, and the Captain and Maria's Something Good, which led to a similar outcome.

The bus goes past the Nonnberg Abbey, where both on-screen Maria and her real-life inspiration spent time as they considered whether to take the vows of a nun. Maria married the Captain there in 1927. The film wedding, however, set in 1938, is shot in the grander Mondsee cathedral, about a 25 minute drive out of Salzburg. The cathedral is smaller than the filming would suggest.

Tour guide Sharron is at her best during these extended drives, delivering a constant stream of facts on how filming was done, the cast and the reach of the five-time Oscar winning work. The bus driver gets a gentle but constant ribbing, as does Christopher Plummer's alleged fondness for an alcoholic beverage.

And it wouldn't be right if there was no singalong, would it? The travellers range from teens to 70-year-olds, but under Sharron's energetic leadership few fail to find voice during the extensive soundtrack.

Towards the end of the half-day tour the singing makes way for a video about Salzburg, narrated by Charmian Carr. It is easy to forget the cast were all strangers to this modestly-sized city near the German border when they created its defining place in film history.

It was a brilliant tour, bringing to life, again, the special movie and its perfect combination of script, song, cast and location, in what was its 50th anniversary year.

It is always sad to see a child go before her parents, even her on-screen ones. But for someone who spent most of her adult life as an interior designer, Ms Carr can point to an impressive film legacy. The third-highest grossing movie of all time, adjusted for inflation. And more powerfully than that, hours of happiness for generations past and still to come.