Road Trip, Part VI

Thursday, May 26: Most of the day was spent underground, exploring two cave systems in the Black Hills area which are each over a hundred miles long. Wind Cave is named for a strong whistling wind that streams in or out (depending on the prevailing pressure difference between the outside and the inside of the cave) of the small natural opening of the cave system. According to ancient Lakota Sioux legend, all the bison of the American prairie were blown out the bowels of the Earth from the mouth of Wind Cave, and the shape of natural entrance does look uncannily like the head of a bison. A mere thirty miles due northwest, Jewel Cave is more conventional, with larger rooms and expected mineral formations like stalactites and stalagmites and is named for several brilliant formations of feldspar and nailshead spar that resemble so many clusters of sparkling precious stones.

Wind Cave is home to a unique formation called “boxwork,” formed when calcite dissolved in water penetrated cracks in the limestone that is the major component of the structure. When the slightly acidic water eroded the limestone, the calcite fins remained behind in upside-down geometric pigeonhole or post-office box shapes that give the formation its name. Also unique to Wind Cave – its dry interior, unlike the dripping-wet, humid atmosphere associated with most caves.

Perhaps the most fascinating thing about the cave systems is how they are neatly arranged around the Black Hills, both the caves and the hills being created during an ancient subterranean upheaval. It is entirely conceivable that the two cave systems are connected, and form part of a larger system that completely surrounds the hills.

That evening, in anticipation of clement weather, I finally checked out of the motel and moved to Sylvan Lake campground in Custer State Park. Pitching my tent in windy conditions proved a tad trickier than when I had practised it in the comfortable and windless confines of my apartment but I got the better of it after a fifteen-minute struggle. Dinner that night was a hot bowl of Maggi, the inaugural meal on my camping stove.