Abandoned coal mine in Germany. Opened in 1873, closed in April 2000. These cages are called Kaue. It was used by the miners to put their clothes,shoes and private belongings in. They could lever the cage by a chain, and lock it. Each chain had its unique number, counting up to 4700 and more. Gives you an idea of how big this place is. In that time it was a cheap and smart way to create a locker system.