2004 tsunami survivor Christine Conroy 'in whirlpool'
A decade has passed since the Indian Ocean tsunami, when more than 230,000 people were killed by huge waves caused by a massive underwater earthquake.
It was one of the deadliest natural disasters in recorded history.
The death toll rose rapidly, with people killed in 11 countries.
Christine Conroy, from Machynlleth, Powys, was in Sri Lanka when the waves struck. Within moments found herself trapped and desperately fighting for her life.
"I remember saying 'the sea's too high, why is the sea so high?' I started to run away from the sea," she said.
Ms Conroy found herself trapped in a room with the water coming in.
"My head was bobbing against the ceiling and I was swirling round because the force of the incoming water was creating a sort of whirlpool in there."
She was only saved when part of a wall collapse and she was carried out with the escaping water.
In the UK, Gareth Owen, humanitarian director for Save The Children, had a call from his boss telling him to turn on his television to what was being reported.
"By lunchtime I had been across to my parents' farm near Welshpool and I was on my way to Sri Lanka to lead Save The Children's response there," he said.
"We'd never seen anything like it - 30,000 people died in Sri Lanka alone.
"Many of those people had been living on the beaches. They were literally washed away never to be seen again."
But the tsunami had not just caused devastation in Sri Lanka and Indonesia, it killed thousands in places as far away as India, Somalia and Malaysia.
Ch Supt Alun Thomas from Gwent Police was sent to Thailand to help identify bodies.
"We were working in a temporary mortuary up towards the Burmese border in temperatures that we don't ever achieve in the UK, in suits and Wellington boots and all the masks you have got to wear when you are dealing with dead bodies," he said.
In Wales, efforts were underway to collect aid to send to the affected area.
The Sri Lankan Association of South Wales sent several shipping containers of aid.
But it was not the only way people in Wales were helping victims of the tsunami 10 years ago.
Plans were being drawn up to stage the tsunami relief charity at the Millennium Stadium in Cardiff, a concert that at the time was the biggest held in the UK since Live Aid nearly 20 years earlier.
And funding raising efforts to aid areas hit by the tsunami are still continuing to this day - even a decade on.
On Friday, hundreds of bathers will take to the sea in Pembrokeshire to mark the 44th annual Tenby 'Boxing Day' swim.
Hoping to be among them is solicitor Paul Cowper, who 10 years ago was wading through flooded marshes in Sri Lanka with his family.
Their experience led them to setting up their own charity to help those hit by the giant waves - raising £75,000 for the coastal town of Tangalle.
He and supporters will be wearing t-shirts marking the tragic events as they take to the Tenby sea.
"It's a reminder to people that the tsunami took place and that the lives of so many were wiped out or changed as a result," he said.