Deep below the surface of Wales, there is a place called the "Cavern of Lost Souls." The man-made mine has been abandoned since the 1960s, but urban explorers still visit this place for one reason. To check out the amazing mountain of rusted old cars. Stacked on top of each other, nobody quite knows how all the cars ended up at the bottom of a mine shaft. Not only that, but the guys found something very unique...an actual sword!