Three Range Rovers were among the expensive cars damaged on the transporter, with the first car having its roof completely flattened in the crash in Marshall Place, Perth, around 8am on Wednesday.
Elaine Blair was at Perth train station when she heard what she thought was the sound of a scrapyard.
The 46-year-old librarian said: “I was standing outside the front door of Perth train station waiting for my friend to get on the 8.14am train to Glasgow.
“Suddenly there was an almighty bang followed by the sound of glass bottles being emptied outside a bar and metal being mangled into little boxes like you see on American TV programmes about scrap metal yards.
“I walked down the pavement and viewed a huge transporter full of brand new cars who now did not have any roofs.”