The "mountain" on the horizon is not a mountain at all. It's a "chat" pile. One of many huge piles of mine tailings in what was the mining town of Picher, Oklahoma.
The intersection of Oklahoma, Kansas, and Missouri was once home to numerous large lead and zinc mining operations. The mining ceased over 50 years ago. Today, much of the soil and ground water is so severely contaminated with lead that the area was deemed uninhabitable. It comprises four of the largest EPA superfund sites in the United States.
I read about this place a while back and since I live only a couple hours away, I decided to make a quick trip out there. I can only describe the experience as surreal and sobering.
Safety Warning: Exploring places like this, especially alone, can be extremely dangerous. The ground here is so severely undermined that a US Army Corps of Engineers survey determined the entire area is at high risk of imment collapse. There are sinkholes everywhere.
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