(1971, Sean Bury, Anicée Alvina)

Beautifully shot story (with an Elton John soundtrack) of a teenage English boy and an equally teenage French girl falling in love and having a baby in rural France before the police finally find them.
In the opening scenes an RATP Berliet PGR passes the boy in a Paris street:

The pair travel to the Carmargue aboard this elegant Berliet PH4 Airlam of Les Courriers du Midi: