Thanks - that does help a lot. We were up there yesterday, walked out accross the cliff from the Mam Tor side right over to Winnats, visiting every likely rock opening we could see.From what you say, I assume that the remains of the sepuchral cave are the largest of the rocky bits, above the show cave exit with a large stone archway (ie you could walk up and through it if it wern't for the nettles) and remains of blue John seams? There were a few other likely candidates but if it has been quarried to bits, I think this is the one. Got some nice pics too - if this sounds right give me a shout and I'll pop them on tma.
Cheers!