Took a bit of a drive today to the southwestern part of the Black Hills, and after heading west from Custer about half way to the border with Wyoming I stopped to check out Jewel Cave National Monument. Proclaimed a National Monument by Teddy Roosevelt back in 1908, Jewel Cave is currently the fifth longest cave in the entire world and the second longest in the United States with over 220 miles of mapped passageways (Mammoth Cave in Kentucky is first in both of those categories).
I arrived a bit later than I expected which put me behind schedule for registering for the cave tours. With only minutes left before they closed it off, I frantically registered…and made the mistake of registering for the Discovery Tour thinking it was the Scenic Tour. Big difference so make sure you pay attention to save yourself any heartbreak. The Discovery Tour basically just descends the elevator into the cave’s first room called the Target Room and goes no further. Good for those who don’t want to walk or see the entire thing. Bad for those like me who want to see more.
Here’s the best photo I could get of the full Target Room – hard to get wide enough in such a cramped area. There is a large hole in the ceiling of the Target Room (and possibly why it is called that since it looks like a bullseye but I don’t recall some details from the tour so don’t quote me on that), and I believe this leads all the way up to the surface.
Here’s a closer look at the opening in the ceiling. Jewel Cave is a “breathing cave” meaning air enters and exits the cave with changes in atmospheric pressure. Using air volume they have calculated that less than 5% of the total cave length has been discovered, and estimates for total length are somewhere between 4,400-7,300 miles. Wow!
As you may have noticed in previous photos there are numerous calcite crystal formations in this cave and that’s what the “jewels” are. Main formation types are dogtooth spar which is shown here and names for the smaller little “teeth” shaped like dog’s teeth. The other which I will have more photos of later are nailhead spar that have a bigger and more blunted appearance.
After the tour ended I decided to register for the next Scenic Tour and in the time I had to wait I’d explore the rest of the monument. More to come in following posts.
Lat = 43.7309456 , Long = -103.8275375 -- Show at Google Maps
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