There's a bunker in the UK [1] that I went to. Before they could allow visitors they had to add a fire escape. Apparently it took a couple of days to cut a hole

There's a bunker in the UK [1] that I went to. Before they could allow visitors they had to add a fire escape. Apparently it took a couple of days to cut a hole in the wall for this due to how strong it is and that was state of the art diamond cutting equipment. Good day out though. [1] http://www.secretnuclearbunker.com/ http://www.secretnuclearbunker.com/