Caving
Well there are not many things that I would not do. But after seeing a vast amount of caving and pot holing videos the fear of crawling through dark, damp and tight holes has made it one of the least attractive extreme activities to take part in.
In this video it is obvious that the pot holers are struggling to get through to the end. The dialogue shows their struggle as they are pummeling away at rock so they can fit through the very thin gap. The worst part is this is the only way out due to flooding in a different part of the cave. For those who have claustrophobia this would be your worst nightmare. But for those who can withstand tight spaces and receive a massive adrenalin rush from scrambling towards the light i would love to know why?!?