If you drive outside the city of Campton, population less than 400, the low industrial noise of crypto mining rises from the trees. There are steel shipping containers like this all over these hills, right where the old coal mines once stood. And inside, specialized computers race to solve complex math problems—competing to verify bitcoin transactions and earn slivers of digital currency as a reward. For a brief moment, in 2021, it felt like the region had found its next boom—and it had Bitcoin written all over it. At its peak, Kentucky accounted for some 20 percent of the collective computing power dedicated to proof-of-work cryptocurrency mining in the US.