A Welsh village devastated by a landslide which almost wiped out an entire generation will fall silent as people mark the disaster's 50th anniversary.
One hundred and sixteen children died when 150,000 tonnes of coal waste slid down a hillside before smashing into Pantglas Junior School, Aberfan, on October 21 1966. Twenty eight adults also lost their lives.
The Prince of Wales will meet the families of some of those who lost their lives at a reception in the Welsh community, half a century on from the country's darkest day.
Charles will unveil a plaque in memory of the victims of the disaster and sign a book of remembrance, after visiting the Aberfan Memorial Garden on the site of Pantglas School.
Survivors will attend special memorial services in the close-knit Valleys community, while the rest of the country observes a minute's silence.
First Minister of Wales Carwyn Jones said the men, women and schoolchildren who lost their lives should never be forgotten.
"It is a truly heart-breaking moment in our history and no-one who learns about the disaster can fail to be profoundly moved by it," he added.
"Half a century on, I hope the country as a whole will come together, with respect and compassion, to pause for a minute at 9.15am and think of the community of Aberfan."
The disaster unfolded, following days of heavy rain, when excavated mining debris from the Merthyr Vale Colliery was dislodged and came thundering down the hillside on a foggy October morning.
The waste material had been piled high on the side of Mynydd Merthyr - above Aberfan - for years, even though there were numerous underground springs below.
Youngsters in Pantglas Junior were just getting ready for lessons when 1.5 million cubic feet of liquefied slurry crashed into the school and a number of nearby houses with a tsunami-like force.
Survivor Jeff Edwards said the events of that day had stayed with him and his fellow classmates all their lives.
For two hours the eight-year-old was pinned next to a dead girl from his class, with her head next to his face.
He said: "What we've all experienced are classic symptoms of post-traumatic stress disorder. There's no doubt it has affected me on a daily basis.
"I still have nightmares and sometimes suffer from deep bouts of depression."
The tragedy was all the more bitter to deal with given that coal bosses had been warned about "flowslides" prior to the disaster, and despite a 76-day public inquiry, no-one ever faced prosecution or even lost their job.
Insult was added to injury when a protracted row about removing other coal tips saw frustrated locals left with no choice but to take £150,000 out of a memorial fund to pay for the clean-up bill. The money was eventually returned, but only after decades of campaigning.
Plaid Cymru's leader Leanne Wood said the events before and after the disaster had changed the close-knit community forever.
She said: "The lives of an entire generation in the village were extinguished before they reached their prime.
"A whole generation of adults and grandparents were denied the chance to see their children grow up.
"Even half a century on, the facts of the Aberfan disaster are no less shocking, and resonate throughout Wales."
Ms Wood said the people of Aberfan should be commended for the dignity and bravery they have shown ever since the disaster.
She added: "They endured unimaginable sorrow but maintained a community spirit and built a support network within the village which helped get each other through their ordeal."
That community spirit will once again come to the fore - and in the glare of the world's media - on the 50th anniversary.
Services of remembrance will take place in a number of local churches as well as on the site of the old school, which has now been turned into a memorial garden.
The Assistant Bishop of Llandaff, David Wilbourne, will officiate at one of the services in Aberfan today.
He said: "This is a time for us to come together as a community, sharing grief which is still so sore, despite the passage of time, and giving thanks for the lives of every one of those who died in the disaster."