Thanks, Jenny. I'm not so sure about Peak? Some have mentioned Wookey as a contender. Whatever it was meant to be I think it looks like a body of water and very fanciful to the point of fantasy!
If I were writing a guide to multiple Show Caves, with a drawing rather than a photo for the cover, I'd deliberately make the drawing a composite of several caves. Make it look more interesting and avoid appearing prioritise one cave.