King Charles added: “Throughout all this, and through all the years, your unconquerable spirit has shone all the more brightly for the darkness which it has overcome.
“No one should ever have to bear what you, as a community, have endured, but no one could have borne it with greater strength, resilience, or hope.
“Please know how deeply we feel with your sorrow, how greatly we admire your strength, and how you will, always, be in our hearts.”
Jeff Edwards, who survived the disaster as an eight-year-old pupil, said in a speech that October 21 1966 was “forever etched into our memory, a day of unimaginable tragedy and loss that changed the lives of families and the community forever”.
“Yet, amidst the terrible sorrow, we were comforted by those who came to stand with us to share our grief and offer their support,” he said.
“The presence of members of the royal family in those difficult years became a lasting and deeply valued part of Aberfan’s history.”