I didn't know Cornwall was a mining center. I thought, "I wonder if there are any good collections of old mining structures and machinery" and then found this [1]. Thanks, old internet! I hope you don't get killed by the walled gardens.
Edit: s/is/was/ and hear Steve Knightley's song "Cousin Jack".
Yep, for 4,000 or so years! Cornish tin made its way into lots of Bronze Age goods. It’s amazing to me the extent of trade that long ago, where Cornish tin made its way into the Mediterranean and beyond.