Nearly 1,000ft below the Chihuahua Desert in Mexico, this cave was discovered by two brothers drilling in the Naica lead and silver mine.
It is an eerie sight.
Up to 170 giant, luminous obelisks - the biggest is 37.4ft long and the equivalent height of six men - jut across the grotto like tangled pillars of light; and the damp rock of their walls is covered with yet more flawless clusters of blade-sharp crystal.
The crystals themselves are created by hydrothermal fluids originating from the magma chambers below or made of gypsum/ selenite. Moreover, some crystals were formed over a span of about half a million years in a hot water solution, saturated with minerals.