Oravikoski's zinc, nickel and copper deposit, located Northwest of the famous Leppävirta international dump pit was discovered in 1954 by a local person who reported his finding further. Out¤kumpu Oy started exploring the area and established a mine, which started operation in 1957. Its official name was Kotalahti, even though that's not the exact location. Mining ended in 1987, but there has been talk about re-opening the mine.

Soon after closing the caves were exploded full of water, but buildings above ground remain. Some of them are used, some not. The area has operated as a kind of test platform for new soil cleaning techniques. It's still under restoration (cleaning). The large open excavation pit provides a good pond for divers.

Trivial fact to know: singer/songwriter Mikko Kuustonen spent his childhood in this mine village.