Apparently the locals have spent 12 hours underground & not found the end:
http://www.channel4.com/programmes/walking-the-americas/on-demand/64332-004
Mike
http://www.channel4.com/programmes/walking-the-americas/on-demand/64332-004
Mike

Anjana Khatwa, award winning presenter and writer: "The Whispers of Rock: Stories from the Earth". Vince Simmonds, archeologist and cave explorer: "Echoes of the Ice Age: A Pleistocene Record from Mendip Cave Deposits" Of particular interest will be the recent find, the Woolly Rhino Skull that is now in Wells Museum. Owen Dukes - Geologist (Tarmac) "Mendip Mineral Resources"