William Wallace was played in the film Braveheart by Mel Gibson
Gruesome posters about William Wallace are too shocking for general display in their current form, the advertising standards watchdog has ruled.
Four posters showing a severed arm, open sores and ligature marks appeared in Edinburgh, the Advertising Standards Authority (ASA) said.
Three people complained the Edinburgh Dungeon William Wallace exhibition posters were offensive and distressing.
Merlin Entertainments said it was using the Dungeon's "humorous tone of voice".
The ASA said Merlin Entertainments (Dungeons) Ltd had explained that the Edinburgh Dungeon was about having fun with history's "more horrible topics" and the new William Wallace exhibition focused on his execution.
The company said it was not commonly known that he was hung, drawn and quartered with his limbs displayed separately in Newcastle, Berwick, Stirling and Perth.
They said they had wanted to acknowledge this in marketing material for the exhibition without giving "too much away" and using the Dungeon's "distinctive humorous tone of voice".
A similar poster, featuring a severed finger pointing in the direction of the Dungeon, in the same street in 2006, had been used without complaint, Merlin added.
The ASA said it recognised the posters were intended to be "darkly humorous" and were unlikely to cause serious or widespread offence to adults.
But upholding the objections from the three complainants, it said: "We noted... the limbs on each poster appeared very badly maimed with realistic ligature marks and open wounds, which were explicitly horrific in their portrayal and the graphic depiction of torture they represented.
"Therefore, although we acknowledged that it was clear to adults that the posters represented a display at the Edinburgh Dungeon, we considered that the images could cause distress to young children, who were likely only to focus on the images and would not understand their meaning or that they were intended to be humorous.
"We concluded, therefore, that in the context of an untargeted medium such as a poster where they could be seen by a general audience including children, the images were too shocking and were, therefore, irresponsible."
The posters have been removed.