An American student who was leading friends up Mount Snowdon slipped and plunged 500ft to his death off an icy ridge.
Jared Maillet, 21, volunteered to go first across the ridge in an endurance challenge but his fellow climbers could only watch in horror as he fell.
The exchange student was taking part in a race to climb all of the peaks above 3,000ft in 24 hours in Snowdonia, North Wales.
A Sea King search and rescue helicopter was called from RAF Valley in Anglesey - where Prince William works as a rescue pilot - but it was too late.
Jarred, from Maine, US, was studying sustainability and urban planning at Arizona State University.
He was an exchange student studying at Manchester University when he started exploring the peaks in nearby Snowdonia and the Yorkshire Dales.
His heartbroken sister Christie, 23, said: 'He was with his hiking group, and decided to take the lead - because that is what he does. He slipped on a patch of ice and he fell off of a cliff.
'I don't like thinking about how he died, so I am thinking of it this way - he took the lead because he is a leader.
'He potentially saved someone else from slipping off that cliff. I'd like to think he passed out immediately and felt no pain or fear.
'The only comforting thing is that he was not cold and alone. He was loved by so many people, and no one will forget him. I hope we all can live like he did.
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Jared's body was found on Saturday by other walkers on a ridge at 2,500ft near a precarious route known as Parson's Nose.
Adventurer: The student, 21, from Arizona State University was an exchange student at Manchester University
His Facebook page shows Jared as a fun-loving young man who loved being out in the elements.
Alongside a picture of him sitting in front of a snowy mountain landscape he wrote: 'I sat there for a few minutes at the edge of that drop off and was getting blasted by winds.
'I was seriously just dumbstruck by the scale, beauty, and rawness of the landscape.'
Another striking image shows the young student balancing on the top of a peak with the comment: 'Pretty wicked winds up there.'
To complete the Welsh 3000 challenge people have to reach the top of all 15 mountains over 3000ft in Wales within the space of 24 hours, without using any form of transport.
Accident spot: Parson's Nose on Mount Snowdon which is near where the accident happened. The student fell from a ridge which was covered in ice
Explorer: Jared Maillet, 21, from Maine, US, was trying to complete the Welsh 3000 challenge where people have to reach the top of all 15 mountains over 3000ft in Wales within the space of 24 hours
Tragedy: The student fell to his death while climbing Snowdon in North Wales
The 30-mile hike is described on the challenge website as 'extremely tough' and 'only suitable for very fit and experienced mountain walkers'.
The Welsh 3000 website warns walkers: 'Navigation can also be problematic without previous knowledge of this area of Snowdonia.
'Additionally, one mountain, Crib Goch, is very exposed - several people have died on it.
'This challenge is often underestimated - you need to be very fit to walk it in 24 hours.'
Arizona State University is today helping return Jared's body to the USA for a family funeral.
His sister Christie said: 'Jared and I had actually discussed not too long ago that both of us wanted to be 'turned into trees' when we passed away.
'There are biodegradable urns that contain tree seeds which you can plant and have eventually grow into a tree.
'Jared was completely into this idea. He didn't want to be buried in a coffin, he wanted to be a tree, and a tree he will be.'
Peak: The tragedy happened on Mount Snowdon, the tallest mountain in Wales on a ridge at 2,500ft near a precarious route known as Parson's Nose
Adventurer: Jared sits on top of a rock looking at the breathtaking view on an earlier trip