Eleven climbers appeared to have died on the world's second highest mountain K2.

It was one of the deadliest days in mountaineering history.

Rock falls, avalanches.

Huge pieces of ice. All are big enough to kill you.

He just flew out into Devoid and he was gone.

How did it all go so wrong?

And is it really worth risking death to feel alive?

Why would somebody pay to go to a place called the death cell on a vacation?

Extreme.

Peak Danger.

With me, Natalia Melman Petrazella.

Listen to the full series now.

First on BBC Sounds.

BBC Sounds, music, radio, podcasts.

It's a wonderfully warm March day, and I've come to a wooded area.

Just outside Bristol called Abbott's Pool, it's very popular with walkers.

We've got beautiful paths running through it.

Originally it was a fish farming area for the local monks,

but in Victorian times it was a designated walking area.

And as well as the trees, you've got the very soothing sound of water.

And this is what the waterfall sounds like like from the outside but what about from the inside

I've come here to meet a sound recordist called Ellie Williams and she has for our benefit

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