canyonwalker | (Reply)

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Very cool! Do always love those beams of sunlight coming down or peeking out in the distance.

Re historical graffiti - last spring we went to Mammoth Caves in Kentucky, which is the longest connected cave system in the entire world at 400 miles and they're still finding more of it. We had one tour (tours only) with an area of cool rock formations, and then the main tour was the historical one. Around 1800 or so, they started mining it for guano, refining potassium nitrate for saltpeter, for gunpowder (and maybe agricultural uses too?). For decades this was a major activity, with 24/7 work, so there are enormous tunnels, minecart rails, smoke stains on the ceiling, and so on - not cool rock formations, but both cave + history for sure. There's lots of graffiti as well, which is what made me think of this. Eventually they transitioned from mining to tourism. (They used to have boat tours through the caves, but that was eventually deemed too destructive to the caves and dangerous for people.)

https://www.nps.gov/articles/000/saltpetre-mining.htm