Unesco World Heritage status for amazing crystal caves in Mexico?
Superman's secret lair? No, but you'd be forgiven for thinking these crystal caves were the haunt of the superhero.
Two miners looking for lead stumbled across these amazing beams of gypsum that have been growing for hundreds of thousands of years in caves below Naica in Mexico.
And now, scientists are petitioning for Unesco World Heritage status to protect the unique structure for generations to come.
Some of the crystals measure up to 11 metres, and the mine is so big you could drive a car through it.
The formation of the beams 290 metres below the surface, occurred when super-heated water began cooling and became saturated with gypsum.
Juanma Garcia Ruiz, a geologist from Spain's Instituto Andaluz de Las Ciencias de la Tierra, who has studied at the mine, told the Daily Mail: 'They're really one of the Wonders of the World.'
He added: 'The crystals need to be preserved much better.
'They really are something amazing and I think there is still people in Mexico who don't know how important it is to preserve them as much as possible.
'I'm trying to convince the people of Mexico to claim Naica for Unesco World Heritage site.
'Naica is very unique and the chance of having another one on the planet is very low.'