2013 Carlsbad National Park, New Mexico

Carlsbad Caverns National Park is located in the Guadalupe Mountains in southeastern New Mexico. This region lay underneath the arm of an ancient sea some 250 million years ago. A 400 mile long limestone reef in the form of a horseshoe built up near the shoreline probably some hundreds of feet in height. Eventually, the sea withdrew and this area was overlain by thousands of feet of sediment. Approximately 15 to 20 million years ago, this area uplifted and erosion began. Sulfuric acid began seeping into cracks in the reef enlarging them into caverns such as Carlsbad. The cavern system actually extends at least 30 miles but 3 miles of the system may be toured on a paved trail. This part of the cave system is lit with interior lighting of various colors to enhance the visitor's experience. The temperature of the cavern systems remains a constant 56 degrees F. The day we toured the cave the outside temperature was 103. Carlsbad is actually one of several hundred caves found in the 400 mile long reef and has been known about since the early 1900s.

The main cavern trail is unguided but has sign posts along the way and a telephone at one point. Access is gained either through the cave entrance, a long and difficult hike, or by elevator located within the visitor center. We took the elevator. It descends 750 ft in one minute (one way). Rangers do patrol the trail. Other routes within the cave system are guided but the visitor must be able to crawl through tunnels with flashlights and rappel down 60 ft cliffs. Our trip through the main cavern occurred in June 2013.