Mammoth Cave

(This column was first published in the September 9, 2002 Buffalo News.)

For years Doris and I have driven down the I-65 expressway to my wife’s family gatherings in Alabama. Finally this year after bypassing Kentucky’s Mammoth Cave National Park so many times, we stopped and I spent several hours touring the caverns.

I have a problem with confined spaces. I’m never really comfortable in airplanes and, once I bought my ticket for a cave tour, the idea of going underground set me on edge.

Oddly, however, the conditions outside at the time of my visit took care of my concern. While my group was riding the bus to the cave entrance, the thick clouds burst. The rain was so heavy it was as though we were making our way underwater. Lightning was almost constant and immediate thunder shook the bus.

So when, after a ten-yard dash through the downpour, we entered the cave, it was like moving into a quiet Eden. The silence and the close walls were not oppressive as I had expected; rather, I found them protective after the out-of-doors violence. My claustrophobia was gone. Even when we had to squeeze through narrow passages I felt no threat.

Our too brief hour-long tour was extremely interesting, our guide Gabe Esters wonderfully informative. He explained how the formations were created — most by the action of water over limestone. He pointed out the bats hanging in small clusters overhead. He told us of hundreds of miles of caves, over 365 already explored, their passageways tangled like spaghetti in multiple layers. But best of all he provided the history of these caves.

Here is some of that story.

It began some 325 million years ago when this area was covered by a warm sea. Dead organisms — plants, fish, even sharks — settled into the muck, quite a bit of muck in fact. Over time chemical processes and pressure turned it into limestone 600 feet deep.

Then as the sea drained away, a river mouth deposited a 50 foot layer of silt that became sandstone and shale, encasing the limestone below and protecting it for millennia. Only ten million years ago was this capstone breached by erosion and the limestone opened to the action of its greatest enemy — rainwater. Passing through the soil the water picked up carbon dioxide to become a weak carbonic acid, just strong enough to eat away at the limestone. Over more thousands of years it carved out these passages creating five levels of caves in the process.

That was, of course, pre-history. Ancient Native Americans discovered the caves about 4000 years ago and left evidence of their civilization including pictographs. European settlers rediscovered the caves in about 1800. Little attention was paid to them until 1812 when their calcium nitrate was mined, refined into potassium nitrate, and combined with sulfur and charcoal to produce gunpowder. This discovery proved critical for the young United States because the British cut off our foreign supplies of gunpowder during the War of 1812.

Only later did the caves become a private tourist attraction and finally in 1941 a national park.

Gabe finished his narration and asked for questions. A young girl asked what I was afraid to bring up: What would happen if there was an earthquake? Our guide responded that there had been a major earthquake in 1812. That shock, believed to have been almost 9 on the Richter Scale, frightened the miners working underground. But when they raced out of the cave, they found much greater destruction above ground: trees down, houses shaken apart, a bleak scene. Being in the cave wasn’t so bad after all.

Mine was a rewarding experience. I recommend it.-- Gerry Rising