Who left these marks and what were they afraid of ? Image Credit: YouTube / Craswell Crags
Strange etchings on the walls of Creswell Crags in England were created to trap or repel evil forces.
Dating back as far as medieval times, the symbols had been seen before in the caves but had, until now, been dismissed as mere graffiti left by relatively recent explorers.
It wasn't until a group from the Subterranea Britannica organization visited the caves that the true significance of the symbols and marks was actually realized.
The etchings are believed to be apotropaic marks - protective symbols scrawled on the walls in an effort to repel or contain the 'evil' forces that their creators had believed resided within.
"It could be fairies, witches, whatever you were fearful of, it was going to be down there," said Alison Fearn from the University of Leicester.
The caves, which were thought to have been occupied by Neanderthals as far back as 50,000 years ago, remain a popular - and eerie - place for research and investigation.
"Death and disease were everyday companions and evil forces could readily be imagined in the dark," said Duncan Wilson, chief executive of Historic England. "We can only speculate on what it was the people of Creswell feared might emerge from the underworld into these caves."