The 'natural' entryway is home to more than a million bats. We went during the day so we didn't get to see them fly out (or I don't think Audrey would have gone in).
750 feet underground in the Carlsbad Caverns, the slow drip of water creates these deposits of calcium carbonate. As rain water passes through the limestone rock between the ground and caverns, it becomes acidic and absorbs calcite. When this water reaches the ceiling of the cavern, it can no longer hold the calcite, leaving it either on the ceiling or floor of the cavern depending on how fast the water falls and other factors. This process, over millions of years, creates various formations as can be seen here. Yep, with Ben along...that's about what the four hour walking tour sounded like.
The cave has something like 83 caves and the Big Room is something like 14 football fields (I'm going off memory here). Our kids were exhausted but loved the names (fairy land, doll's theatre, lion's tail). Once done you get a refreshing drink at the 'restaurant' and then ride the elevator up (with the lights off, it's awesome to see all 750 ft swooshing by). I really wish we would have had our nice camera. We took a few from a disposable but due to my luck this week my computer isn't letting me put them up.
Tons of it reminded me of the Passage to Mordor, or Khazad-dum in Moria. My kids thought that the little lights placed in various high places were lightbulb fairies.
