The Peak District in Derbyshire is a very fine scenic area with a number of large caverns,some natural and some the result of mining ,mainly lead.The ones we visited were Blue John ,where the only semiprecious mineral in the UK occurs.Speedwell with its' flooded tunnels and the most famous The Devils Arse,where an underground stream emerges into a gully and by so doing at certain times when the water is in flood emmits a rather strange noise.Apparently Queen Victoria visited the place twice ,whether she was amused or not isn't recorded.