California Bound: Day Three

(Saturday, December 31, 2006)

A day under Kentucky. The first stop today for my Dad and I was Mammoth Caves National Park in Kentucky. We had been here once before when I was a kid. I really wanted to get back and do another tour.

The day before I had used me brand new cell phone to call ahead about tour tickets. According to the service there were only two tours running. Turns out in winter they don't run most of the tours. In actuality there were 4. However they weren't that busy. Of the 114 spots on the tour I had selected there where only 8 advanced bookings. All the literature on the park says book in advance so you won't be disappointed. With a 106 opening I decided it was unnecessary to book in advance. In Summer I can believe it's a very good idea to book in advance.

The tour we ended up taking was the Frozen Niagara Tour. The tour I really wanted to take was the River Styx Cave Tour, which goes into the deepest part of the caves. Unfortunately it wasn't being offered at this time of year. There used to be a tour that had boats that you rode on the river. This is the tour we tried to take when I visited as a kid, but we just missed out on the timing.

I heard two different reasons for the boat tour being discontinued. The official one seems to be it was affecting the natural wild life in the cave. The less official reason given by a ranger we talked to was the cave was getting unpredictable flooding which was both dangerous and damaging the docks and walkways. He then went on to describe a few tours he was on when he had to get the boats out of there fast because the water was rising. He said the final year they ran the tour they only managed to run it 18 days during the season.

The Frozen Niagara Tour starts with a bus ride out into the woods. From the 8 people who had booked in advance the group grew to around 50. After getting off the bus we all walked down a small path into a depression in the ground. Likely a sink hole. At the bottom was a rather surreal looking stainless steal door.

This was our tour guide April. She did a wonderful job, and had a lovely southern accent. There was a second ranger there who took up the rear of the tour group. He had some good stories as well.

The first part of the tour is through a man made tunnel which was blasted out of the rock. This was only a short distance though. Then began the natural cave, and a long decent down. The stairway was stainless steal. It was apparently installed in the 90s at a cost of over $1000 a step. They replaced the wooden stairs that were there before.

The story behind the installation of the new stairs was quite interesting. They had to go through several contractors before they could find once that would do the job in a way they could except. The resulting contractor turned out to be a submarine refitter. They could work in tightly confined spaces, and only wanted to do a limited amount of blasting.

There were more them 300 steps down in this part of the cave.

Once at the bottom of this set of stairs the rest of the tour was pretty flat. This makes sense. The layers of rock are pretty level in this area and once you reach a cave bearing layer the cave is going to follow it.

One of the things I found interesting was there are no recorded rock falls in this part of the cave. There were some pretty precarious looking rocks though. Apparently the there was a large rock break free in the natural entrance area one particularly cold winter. I think they said the piece was about the size of a car.

One thing thats kind of freaky to me is the large perfectly flat spans of rock across the ceiling. And this tour doesn't have the largest of them. It makes sense that they form this way. The layers of rock are very flat, so as the layers below fall away they will reveal the bottom side of the layer above. If a layer is particularly strong it will form a large flat ceiling over time. It's impressive how large and how flat it can be.

After working our way through a long series of caverns referred to as dormant caves, we came to a section of dieing cave. This is the Frozen Niagara part of the tour. This is where water is actively depositing material in the cave forming classic cave features like stalactites and stalagmite.

The reason this is referred to as dying cave is because it is actively being filled in. Eventually these deposits will close in the cave completely. Living cave is where the cave is actively being expanded by water erosion.

The reason it's called Frozen Niagara is somewhat obvious. It hard to capture the full extend of it with a camera, but the rock does look like a massive cascade of water over a cliff.

Finally we exited the cave through another surreal looking door. I don't have a picture of it, but it was a revolving door, and out into the woods again.

The reason for the revolving door is keep air from entering the cave. The wild life in the cave does much better when the cave is breathing naturally. Having a large opening throws things off. The cave maintains a very constant temperature. Many of the creatures, can't handle more then a few degrees of temperature changes.

After the tour we walked down to view the natural entrance to the cave. This is where most tours start, but is a couple of miles from the section of cave we viewed. The natural entrance is very much the classic cave entrance. We couldn't go far inside though as it was closed off to guided tours in the winter.

We finished up at the park a little after noon. We then headed off for lunch and on to Memphis Tennessee. Along the way we stopped at the John Cash rest stop on the Music Highway. Or I-40 as it's shown on most maps. This highway would take us the rest of the way across the country.