The Black Hills 22-23 Sept

It was cold again as we got up but as we drove towards Hot Springs (that is the name of a town at the South end of the Black Hills in South Dakota) the sun came out, the clouds rolled away and we were left with a beautiful day; not hot, just right. The Black Hills were formed when there was an upwelling of magma that pushed the top sedimentary layers up but never erupted. They are now covered in Ponderosa pine which makes them look black from afar. After the grey, yellow and light greens of the prairies they are quite a dramatic, looming feature on the horizon. Hot Springs is so called because of the 87F spring water that erupts from the hillside and that was trapped in the early 1900s to make a pool. It is not sulphurous but clear water, so quite unusual for a hot spring. We were thinking of going in but it was full of teenagers so we gave it a miss!
We visited an archaeological site where up to 64 (so far) mammoth skeletons have been found. There appears to have once been a cave system under that part of the hills that then collapsed to form a sink hole that slowly filled with the warm waters. Because of the temperature of the water the small lake that formed always had good grasses growing around its shores even in the depths of winter. This seemed to attract the mammoths who then fell in; or at least could not get out again; and so they have remained. Eventually the sink hole silted up, there is evidence that once muddy it was still used as a wallow because there are footprints in the layers. Then the land around the sinkhole started to erode away but the silted area didn't because it was so compact, and so what was once a hollow became a hill. In 1980-something a land developer decided to flatten the hill but as the digger cut into it they found lots of bones and so stopped and called in the archaeologists. Since then they have gone down about 30 feet, but test drilling show that there is at least another 60ft of sinkhole to uncover and that there are bones all the way down. They reckon it will take at least another 35 years to get down that far! The site is great, the whole sinkhole is now inside a building and the dig continues in front of you. Lots of the bones have been left in situ so that you can see what is going on.
Amazingly every single mammoth that has been found so far (3 woolly and the rest non-woolly) have been male, but of all different ages. They have also found a short faced giant bear, American lions, some deer, and many small mammals such as mice and mink. Did you know (I didn't) that, like elephants, mammoths only have four teeth, but that they have 6 sets (of 4) in their lifetimes. The sets don't grow up out of the gum like ours but sort of move in from the back, like on a conveyor belt, and as they move forward they push the old teeth out the front!
Our fill of bones, we decided to head North through the hills to Wind Cave National Park. This was the first ever state park designated to protect a cave and was the 7th state park in the US. It now has reintroduced wild Bison (called buffalo locally) which we were fortunate enough to see really close up, and we also stopped to watch another Prairie dog community (they are soooooo cute). Wind Cave is currently the 4th largest cave in the world (it was the 8th only 10 years ago but they keep on finding more and more tunnels, one estimate is that they have only found 5% of it so far!) So far they have mapped 134 miles of tunnels (and are adding about 3 miles each year), 90% of what they have found so far is situated within a 1 square mile area on the surface! It is called Wind Cave because the one entrance that has been found so far has amazing winds either coming out or going into the cave. Top speed so far recorded is 80mph; all driven by the difference in pressure between the air pressure within the cave and outside the cave; so if there is a low pressure system over the cave (like when we visited) then the wind blows out of the cave; if there is a high, then the wind will blow back into the cave. The natural entrance is only about a foot square and for a few years in the 1890s visitors used to go in and out through there until the people that owned the land saw the opportunity for a tourist attraction and they blasted a door sized entrance through the rock. By 1903 it was realised that the cave was being damaged and so the National Park was made to protect it. The first person to do the most exploring was a 16 year old boy who used to go down with a candle and a piece of rope. Only this year some people trying to map the cave came upon a new tunnel (or so they thought), but at the far end of it they found candle stubs and the boys name written across the ceiling... a 19th century vandal!
Our guide told us how the surveying was done and that 90% of leads (those are entrances to tunnels that have been discovered but not yet explored) are awaiting mapping. The last time one of these leads was explored it lead to 60ft of main tunnel with 23 new leads! The rangers are convinced that when and if they map it all then it will be the longest cave system in the world. We only did 2 hours of exploring but we were amazed at the number of tunnels leading off the passageway we passed along. The cave also has 90% of the world's known samples of Box Work, a type of Calcite (CaCO3) formation a bit like a dessert rose, plus popcorn and geode crystals.
Leaving the cave we drove to Custer through Custer state park which has amazing rock formations amongst the trees. We were treated to a fabulous sunset but will be going back tomorrow to the see the rocks in the daylight... so beautiful.
We decided to treat ourselves to a steak in a restaurant and then parked up our van on a back street and went to sleep at around 8:30pm absolutely exhausted.
In the morning the sun awoke us around 7.30am and we decided we should get up before the town got really busy. I went out of the van with my cup of tea to sit in the sun and immediately opposite our parking spot was a huge sign that said 'Camping not permitted'! Ah well, what is done is done.
We returned along the road that we had come along at sunset the day before and were stopped again and again by breathtaking views of trees and rocks and shadows and light. We spent about 4 hours wending our way through the hills, we were treated to real close up encounters with deer, buffalo (bison), prairie dogs and wild donkeys who stuck their heads in through our windows and a distant (30m or so) viewing of an eagle.
Eventually we reached Keystone in the middle of the Black Hills and about 2 miles from Mount Rushmore. We wandered through old curiosity shops. There were fantastic signs outside nearly each building telling its history. Most were built in the 1890's during the Gold Rush time and have changed very little since then. We went to the Big Thunder Gold mine for a tour. Our guide was an old guy called Jim, slow and full of really interesting anecdotes. We had taken so many photos through the park that we ran out of batteries for the camera so only managed one photo in the entrance to the mine. (we have 2 batteries but one was charging and then the second also ran out!) The Big Thunder mine was a claim of 2 German immigrants who started digging in the late 1880's when they were in their 30s. They chose the spot because it was between two already successful mines. They had no money so had to give away 50% of their future finds in order to secure money to live and to start the mining process. 34 years later they hit a rock of nearly pure iron ore which stopped their progress past 300m into the hill, they couldn't mine to the left as the neighbouring mine was only about 5ft through the rock, and to the right they cut away about 4 metres but then were too close to the neighbouring mine on that side too. Total find in their mine in the 34 years was $200.00. So after the 50% share to their benefactors at the Bismark mine they made the grand sum of $50 each over the 34 years! They were in their 70's and then only one is known of after that as he had 10 children to tell his story. It turns out that he died a rich man after winning several mines (including the Bismark) in Poker games!
The mine had examples of all the old equipment and we were shown how the drilling and blasting was done, shown an example of a very early port-a-potty that was taken down into some of the deeper mines, shown how the equipment worked that crushed and sorted the rock pulled out of the mine and then Tristan did some panning in the grit from the bottom of the stream where all the old mines used to send their water after processing their rock. We now have a small (tiny.. maybe a cm tall) bottle of rose quartz, garnets and gold that Tris found during his panning.
We are now ensconced in a rather posh campsite just past Mount Rushmore, we drove past the monument to get here and got our first glimpse of the carvings.. very impressive.. but we will return in the morning when the light is from the East and will be shining on them rather than from behind them.