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It was a great visit, being inside such a huge cavern made by men with really basic technology is very humbling.
It was a particular thrill to see the veins of coticule snaking through the blue stone (BBW) - I took back a loose chunk and lapped it and it's definitely the same stuff. Bart has it now.
I visited an old bakery which still had it's original sink and draining board carved from a single massive slab of blue stone, they didn't only make crosses from it - it's a great material and was used for much of the construction of the houses round there.