For my first stop on this grand adventure, I drove about 2 hours north of Nashville to Mammoth Cave National Park in Kentucky.  Although I started out on interstates in rush hour, it became a lovely green scenic drive as I neared the park.  Unfortunately, even on a Wednesday morning, the parking lot was absolutely full, and I had to circle for a bit before finally getting lucky and finding a spot.  Also unfortunately, all the cave tours were booked out when I arrived at 11am, except for the self-guided tour of the outer cave.  So deciding which tour to do of the many that they offer wasn’t really a problem!  If you intend to visit, I would recommend getting there quite early, or else seeing if you can book tours ahead of time.

The self guided tour started down a paved path into a sink hole, which in some ways reminded me of the sink holes at Mount Gambier in South Australia, though less developed and enhanced.

The tour traversed several of the outer rooms of the cave system, on a well-paved path that was very necessary due to all of the visitors there.  The caves themselves are cut by water erosion of the native limestone, and although they were quite impressive in size, there were no really interesting rock formations in the outer rooms, as I understand that there are farther in.  For that reason, I would guess that the guided tours are so popular.

The cave was known to the Native Americans, and has been offering tours fro over 200 years.  It’s the world’s longest known cave system, with over 400 miles explored.  The cave has been used for many purposed over the years, but one of my favorites is for tuberculosis, as apparently staying in a cabin built in a cold cave was supposed to cure you!

Another interesting use of the cave was for mining saltpeter.  Soil was dug out of the pit in the picture below, and washed to dissolve the salts.  The salty water was then transported to the surface, where evaporation was used to extract the saltpeter.  The washed soil, which no longer contained the salts, was considered “petered out” and dumped to the side.

Saltpeter is used to make gunpowder, of course, and the War of 1812 was apparently fueled almost entirely with saltpeter from Mammoth Cave.

In case you were wondering, no mammoth bones were found in the cave.  The name comes entirely from the fact that the cave system is mammoth-sized!