Two from me...
...The first being some 30 years before my birth - Grandad, prior to the conception of my dad, was getting on the troop truck ready to ship out, but slipped and broke his leg. His destination was Norway, where all his lorry-mates were minced or captured.

Zooming forward, the location is Swildons Hole, a cave in the Mendips. It's tremendous fun, especially when the water is running a bit high as it was at this particular time. There's a route called the round-trip, which involves negotiating a series of ducks (a low muddy passage, mostly filled with water) and a small sump (a completely submerged passage, which has a rope leading through it. Deep breath, pull rope, out pop).

We decided to do it in reverse, and as the water was higher than usual, we found that all the ducks had become sumps, ie no airspace. They are quite tight and the third one has a hairpin bend in it, so it's not something you can do on a single breath. So we bailed it until there appeared to be a couple of inches of airspace and I volunteered to go first. So I'm on my back in the pool, helmet off and pushed in front, rather like I'm frozen in mid-backstroke. In many respects ducks are worse than sumps, especially if you are claustrophobic - you are supine in a tight, rough tube, 19/20ths of your body under water, with just your eyes and nose peeking out.

On this occasion, we'd bailed so little that my nose was brushing the passage roof, and any ripples caused by too vigorous movements would submerge my eyes. Still, deep breath, take it steady and slow. I got to the hair pin bend and felt my way around it (this is all in pitch black, of course - the light on the helmet being pushed in front of me). Half way around, the roof of the passage dipped enough to deny the already meagre airspace. I unwittingly pushed into it, and was suddenly completely submerged in the cold, muddy water. Instinctively I tried to sit up, but with my face already touching the ceiling, there was nowhere to go, so I just mashed my face into the rock, causing me to yelp, lose my lungful of air, and panic badly. I should have just pushed on through - five more feet and I'd have been in open passage again - lizard brain told me to reverse out. But I'm stuck on the bend - my large battery on my belt is caught on the wall, and I'm going to drown in 10 inches of water, which is a stupid way to die.

Thrashing, I free the battery and wriggle desperately, my body keeps trying to sit up - it's really not helping. Flailing legs gain some purchase and I drag/push myself back the way I've just come. I can feel a pull on my boot - my buddies have realised there's a problem, and as soon as my feet are visible, reached in. I'm pulled free, puking and sobbing with fright.

Bailing the duck has filled the preceding ducks, so turning back is not practical, and if I think about it, I'm going to panic big time. So straight back in. This time, there's airspace all the way through - my thrashing had shifted enough water, and I'm through.
(Mousy Tongue ...Generally bemused by life..., Sat 21 Aug 2010, 19:46, 14 replies)

oh my god
well described, I felt your dread there.... congrats on getting out!
( Rotating Wobbly Hat That's not a banana. THIS is a banana., Sat 21 Aug 2010, 20:13, closed)

Click
That is eerily close to my worst nightmare. My heart's pounding here on the sofa!
( daikoku has been on a ragga tip since, Sat 21 Aug 2010, 22:26, closed)

Flipping heck!
This is EXACTLY why you would never get me down a hole! :-O
( Slippery Jim Seeking a psychotic lady for fun & sex & crime., Sat 21 Aug 2010, 22:54, closed)

I had to really concentrate to understand this
and then it terrified me.
(Falstaff's Spiritual Successor, Sat 21 Aug 2010, 23:42, closed)

see, this is why i could never do this
despite the fact that i actually like small spaces
( Smash Monkey lowering the tone of the whole internet, Sun 22 Aug 2010, 0:41, closed)

And you do this sort of thing for FUN?

( seeballs Doo da da doo da da doo da da doo, da da doo da do, Sun 22 Aug 2010, 7:56, closed)

Clicky
Have a click for reminding me how much fun I had in the Mendips 30 odd years ago, I have drunk too much beer to do it now. Did you ever 'surf' the double pots?
(johnners hitting things with hammers until they work, Sun 22 Aug 2010, 10:08, closed)

Double Pots...?
Hell, yes - great fun to tell a novice that they were only about a foot deep...
(Mousy Tongue ...Generally bemused by life..., Sun 22 Aug 2010, 18:22, closed)

O to the M to the F to the G
Another heart pounding here. It takes all sorts to make a world but fuck me, you call this fun ?
Mad as a brush, you are !
Click.
(womanwhocanonlylivewithdogs, Sun 22 Aug 2010, 17:35, closed)

Christ
that was so well told I actually was't sure you were going to make it!

And then I realised what was going through my head, and felt like a right twat!

*click*
( the pink chicken sniffer sniffs pink chickens., Mon 23 Aug 2010, 13:12, closed)

^^ everything said above ^^
I went potholing once... thought it would be a laugh... about ten minutes in I discovered that I really, really don't want to ever do it again. Ever. Apparently I broke some kind of record getting back to the surface again.

The idea of being trapped in a narrow, twisty, water-filled, pitch-black tunnel with almost no air... gaaagghhhh, I'm having a panic attack right now, sitting at a desk in a shaft of sunlight. I can't even conceive how bad the reality would be.
(moon monkey is busy making memories worth repressing, Mon 23 Aug 2010, 16:27, closed)

Argh.
I've had nightmares about potholing ever since there was an incident shown on "999 Lifesavers" years ago. Reading the passage in 'The Weirdstone of Brisingamen', in which a group of people have to wriggle through a seemingly endless passage underground, gives me the cold sweats.
(The Empress it seems you CAN polish a turd!, Mon 23 Aug 2010, 19:09, closed)

I got exactly the same feeling
that I had reading this as I did when I read 'Weirdstone' many, many years ago. My worst nightmare.

Click..
( His Popiness the Hole Invaded Poland on, Mon 23 Aug 2010, 21:59, closed)

I feel sick now
You just did a wonderful job of describing my worst nightmare and, in doing so, made me feel physically sick with dread. Well deserved click.
(lardyboy Next stop, Fissplap Central, Wed 25 Aug 2010, 16:48, closed)