I have only been into Beaucette once but it was certainly an interesting experience. The HM guides you in by vhf and when I first called him up he said "do exactly as I say, and don't touch your VHF, just raise your arm to show that you understand my directions". He then guided me towards a wall of rock but at the last minute the entrance appeared and in we went.
Inside it's like something out of a James Bond movie.
"Our business in life is not to succeed but to continue to fail in good spirits." RLS