Useful Information

Location: Carlsbad Caverns NP, NM. 10 km off Highway 62/180.
Open: Closed!
Fee: Closed!
Classification: SpeleologyKarst cave
Light: none
Dimension: D=489 m, L=217,261 m.
Guided tours: none
Bibliography: Stephen Reames,Lawrence Fish, Paul Burger, Patricia Kambesis (1999):
Deep Secrets, The Discovery and Exploration of Lechuguilla Cave,
Cave Books, ISBN: 0939748282 (Paperback), 0939748185 (Hardcover)
WorldHomepage | WorldHardcover at Amazon.com | WorldPaperback at Amazon.com
National Geographic's Mysteries Underground, National Geographic Video (VHS), 1997. buy at Amazon.com
Address: Carlsbad Caverns National Park, 3225 National Parks Hwy., Carlsbad, NM 88220, Tel: +1-505-785-2232, Fax: +1-505-785-2302. E-mail: contact
Tour reservations, Tel: 1-800-967-2283, international Tel: +1-301-722-1257.
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1914 mining claim for guano filed.
1984 start of digging by a group of Colorado cavers.
26-MAY-1986 entrance to cave below discovered.


Lechuguilla Cave is the deepest and the fourth longest limestone cave in the United States. It is named after the agave Lechuguilla, a member of the family Agavaceae, that grows all around the cave entrance.

Lechuguilla Cave is called the most beautiful cave of the World, as it is full of speleothems and troglobionts found nowhere else in the world. This is the reason, why it is very difficult to visit Lechuguilla. Because it is the most beautiful cave of the world, the National Park authorities try to keep it in an undisturbed state. Speleologists have to proof that they are able and willing to take care of the cave. For a few years, less than ten expeditions per year were allowed. After the theft of a very famous cave pearl, the cave was closed completely for several years!

The recent exploration and scientific discoveries in Lechuguilla Cave, and other caves in the park, hold immense potential for scientific research. But still there is a drawback: the caves are extremely fractile, as especially the selenite formations may be destroyed even by slightest changes in humidity. In some cases it was reported that a group of caver breathing in a huge hall for some time caused the collapse of fragile gypsum chandeliers.

Lechuguilla Cave was formed by processes, which differ from regular karstification. Limestone requires an agent, an acid, so water is able to directly dissolve the rock. Normally there is a little bit of carbon dioxide (CO2) in the water which makes it carbonic acid, which is very weak, but still dissolves big cave system over long period of time. But here in Lechuguilla, the chemistry was different, there is a huge amount of cave minerals which contain sulfur. Such minerals are formed by chemical reactions with sulfuric acid. A second strange thing was the enormous cave system, hundreds of kilometers of huge passages and chambers, with actually little connection to the surface drainage system. Karst caves are generally the conduits in a huge drainage system, but Lechuguilla is covered by limestone with almost no caves and there is no obvious drainage system.

The solution of those mysteries was a now theory of cave formation, which differs from classical systems but seem to have relevance to many other cave too. One basic thing is dissolution by sulfuric acid which was formed by the chemical decomposition of nearby oilfield. The oil contains hydrogen sulfide which reacts with ground water. The water body was filled with sulfuric acid, which dissolves huge amounts of limestone, much more than carbonic acid would. The water exchange is slow, so the solution stays underground for a long time which chemical reactions go on and other chemical substances, combination of calcite and sulfur are formed. They start to redeposit, mostly in form of minerals. This explain the enormous amount of sulfur based minerals like gypsum and other rare minerals like hydromagnesite.

This process of speleogenesis (cave formation) requires much less water than classical karstification, which also fits the measurements. It was a completely new theory and caused a sort of creative big bang among cave scientists world wide. Now there wqas no need any more to have a source of dissolvant from the surface. During the last 30 years many new effects and theories were published in scientific literature, which may be called hypogene karstification, solution by chemical reaction of substances which are already underground and are transported by the ground water body.

Another impressive field of scientific research was strongly connected to this new research. There were arguments by old school mineralogists which could not explain the chemical reactions with normal chemistry. There were simply no suitable reactions, although the elements were all there. A new theory postulated a biologic influence by microbes which live underground in fissures of the rock. One problem was, that those microbes were at or below the resolution of regular REMs. But fortunately at the same time the technolgy became better and it was now possible to see those extremophiles.

Extremophiles are bacteria which love extreme habitats. They process various substances to gain energy, for example oxidze sulfur or process it in other ways which produces energy. The chemistry of the microbes produces the substances which create the cave (sulfuric acid) and form the minerals (gypsum, hydromagnesite asf.). Many scientists concetrate on the study of those bacteria, as they hope they developed efficient methods of killing other bacteria, which could quailify as antibiotics. The overall use of this research for pharmacy could be enormous, as much as the revenues.

As a matter of fact the Lachuguilla Cave is not only a beautiful treasure of nature it also started and influenced scientific research in various areas. Now theories of speleogenesis were developed, and the number of papers published on scientific work in the cave is enormous.