Lechuguilla cave was discovered in 1986, when cavers dug open a hole in a long known depression near Carlsbad Cavern in New Mexico, which was long ago mined for salpeter. Little did they know, that they opened one of the most beautiful caves in the world.

Since then not less than 150 km of winding cave passages has been explored, bringing Lechuguilla into the league of the longest caves in the world. Previously unseen - except maybe in the Kap-Kutan cave system - cave formations of marvellous beauty and majestic dimensions were discovered.

Lechuguilla is - together with Kap-Kutan and a few much smaller caves - a member of the rare class of caves leached by sulphuric acid solutions. Limestone, the major host rock for cave formation, is normally slowly dissolved by slightly carbonated water and hence cave formation is mostly a slow process. In Lechuguilla the water was much more acidid due to hydrogen sulfide, which originates from nearby oil bearing sediments. Water and hydrogen sulfide form sulphuric acid and so Lechuguilla was sort of leached out of solid rock by diluted acid. This process is much faster than ordinary cave formation and results in the deposition of large quantities of gypsum in the cave.

In Lechuguilla we find large candelabra like formations composed out of myriads of crystals of gypsum and aragonite, which may reach a dimension of several meters. Though they are composed of generally small crystals, the shear size of the individual crystal aggregates is impressive enough.