I went to Carlsbad Caverns as a teenager and was totally blown away by the size of the caves. The place even has elevators. Explorers are still finding new branches in the complex, and below is the National Park Service release about a recent discovery:

Large Room and Deepest Pit Found in Lechuguilla Cave Date: June 2, 2012

In early May, a team of cave explorers, led by Derek Bristol of Colorado, climbed over 410 feet into a high dome in Lechuguilla Cave, which is a system that is part of the Carlsbad Caverns National Park in New Mexico.

Upon reaching the top, lead climber James Hunter discovered a maze of previously unknown passages, pits and large rooms, which they called collectively, Oz. One large room measured 600 feet long, 100- 150 feet wide, and 75-150 feet tall was called Munchkin Land. Lechuguilla Cave is known worldwide for its large rooms, unusual minerals, massive and fragile cave formations and importance in scientific study.

Since mapping began in 1986, explorers have surveyed over 134.6 miles of cave passages in Lechuguilla Cave. Because of its delicate environment and scientific importance, only about 100 people, usually vetted explorers and scientists, are permitted to enter the cave every year. Ten cavers from Colorado, South Dakota, New Mexico, California and Arizona participated in the eight-day underground expedition that made these discoveries, the greatest amount of distance added to the survey in one day since 1989, according to the National Park Service.

Using laser distance meters, Bristol’s team measured the distance from floor to the final rope anchor of the dome they climbed as 510 feet, making it the deepest pit known in the park. Stan Allison, Carlsbad Caverns National Park cave technician, explained, “to understand the sheer size of this space, imagine that a 51-story tower could fit inside.”

Called the Kansas Twister, the dome was discovered in 2007 as having the potential for further exploration, but a team in 2010 failed to climb beyond 80 feet because the rock walls were too unstable.
For comparison, the Kansas Twister is about half the height of the Chrysler Building in New York City or the John Hancock Building in Chicago. Or for those who have visited the Big Room in Carlsbad Cavern, the Kansas Twister is about twice the height of the Spirit Room Dome, 255 feet high.

Most of this newly found section of Lechuguilla Cave is in a layer of rock called the Yates Formation, which is made up of deep red, orange, and yellow colored rock but has fewer stalactites and stalagmites. Other exploration teams will continue mapping this year, but the next trip to “Oz” will be in 2013.

Geologists or microbiologists may seek permits to study or sample in the uniquely pristine environment.

While recreational tours of Lechuguilla Cave are not allowed, a variety of cave tours, for a range of abilities, and educational programs are available to the public. For more information, visit the park’s website at: www.nps.gov/cave. (6.12.12)