Once again, Steve challenged my sense of adventure and dared me to take the Natural Entrance Route self-guided tour. And, after hearing about all of our blue-haired companions on the King's Palace tour who had already taken it, I was sort of on the spot.  The Carlsbad Caverns National Park official brochure describes this tour as a "self-guiding tour available to visitors with plenty of time and in good physical condition." Time is the one thing we have plenty of; however, I don't think either of us has been described in recent memory (if ever!) as being in good physical condition. But hey, what the heck ... we had our hiking boots on and a bottle of water ... we were good to go! Our plan of the day was to walk the Natural Entrance Route which led to the Rest Area, take the elevator to the surface, have lunch in the Cavern Restaurant, then take the elevator back down and walk the Big Room self-guided tour ... a total of about three miles.

The history of the Carlsbad Caverns indicates that the first recognized explorer discovered the caverns when he became curious about the hundreds of thousands of bats emerging from a cave every day at sundown. A guano mining business developed (it was used as fertilizer) in the late 1800s and continued until about 1940. In fact, the early visitors to the caverns had to descend by way of the same bucket used to haul the guano to the surface! We asked whether the guano is removed by whatever means nowadays ... the answer is no. As such, the estimated pile of guano is about 40 to 60 feet. (Holy bat crap!)

The daily exodus of bats from the "Bat Cave" (Holy guano, Batman!) still draws a huge crowd ... but once again our timing is wrong ... the bats don't return to the cavern until mid-to-late March. Spectators watch from this amphitheater at the Natural Entrance.

Although the path into the caverns is paved, it is steep and not recommended for people with knee problems ... This trail descends more than 750 feet ... and is sometimes really steep and narrow. But it is most definitely worth it ... In order to maintain the feeling of being in a cave, the lighting was designed by a lighting designer from Broadway ... and it is very effective.

This is one of the many pools we saw ... the water was so clear that between the lighting and the clearness of the water, it was hard to tell if many of these pools actually had water in them.

This one was called the "Whale's Mouth" ... can you see it?