Britain's Prince Charles and his wife Camilla have arrived in Mullaghmore, Co Sligo, where his great-uncle was killed in a bombing.
Lord Louis Mountbatten was one of four people who lost their lives in the IRA attack off the coast of the fishing village in 1979.
The royal couple arrived in Mullaghmore at about 5pm to meet others affected by the IRA attack and those involved in the rescue.
Several hundred locals lined the seaside village.
Among those who greeted the prince was Peter McHugh, a lifelong resident of Mullaghmore and one of those most closely associated with efforts to rescue the Mountbatten party.
Last week he described how doors and other materials were used as makeshift stretchers to bring the dead and injured ashore.
The other victims were Lady Doreen Brabourne, 83, the mother-in-law of Mountbatten’s daughter, who died a day later; Nicholas Knatchbull, the earl’s grandson who was 14; and his friend Paul Maxwell, a 15-year-old local boy from Killynure, Enniskillen, who had worked on preparing the royal boat for fishing.
The royals also met Kevin Henry, a retired Garda who was on security detail for Lord Mountbatten when the IRA struck.
He saw the aftermath of the huge bomb from the headland above the village.
Others included local couple Elizabeth and Richard Woodmartin who pulled Timothy Knatchbull from the water after his brother Nicholas suffered fatal injuries.
He accompanied Charles and Camilla on their short tour of Mullaghmore with his wife Isabella.
The Maxwell family, including father John and mother Mary Hornsy, met Charles privately in the Pier Head Hotel, where victims of the bombing were treated once on shore.
Mr McHugh walked with the prince along the lines of well wishers where the royal couple stopped on several occasions to shake hands and exchange greetings.
At the slipway to the harbour, from where Lord Mountbatten set out to sea that fateful morning, Mr McHugh pointed the area around the bay to the prince.
The Prince of Wales told victims of the 30-year Northern Ireland conflict he feels their pain as he spoke about the IRA murdering “the grandfather I never had”.
Charles said time had been a healer for him but his grief gave him a deep understanding of the hurt of others.
“In August 1979, my much-loved great-uncle, Lord Mountbatten, was killed alongside his young grandson and my godson, Nicholas, and his friend, Paul Maxwell, and Nicholas’s grandmother, the Dowager Lady Brabourne.
“At the time I could not imagine how we would come to terms with the anguish of such a deep loss since, for me, Lord Mountbatten represented the grandfather I never had.
“So it seemed as if the foundations of all that we held dear in life had been torn apart irreparably.”
Charles made the remarks at The Model arts centre in Sligo ahead of a peace and reconciliation prayer service in nearby Drumcliffe and a poignant visit to Mullaghmore where the assassination was carried out.
Referring directly to the impact the murder had on him, Charles said: “Through this dreadful experience, though, I now understand in a profound way the agonies borne by so many others in these islands, of whatever faith, denomination or political tradition.”
Charles has previously referred to Lord Mountbatten in his journals as someone who was infinitely special, a confidante who showed enormous affection but also someone who criticised and praised.
As news of the royal assassination reverberated worldwide, 18 British soldiers were blown up in an IRA ambush which became known as the Narrow Water massacre.
He also recalled the thousands of Irish soldiers who died fighting in the First World War and said the centenary commemorations of the fight against Germany provided common ground for Britain and Ireland.
“We all have regrets. As my mother said in Dublin Castle, ’with the benefit of historical hindsight we can all see things which we wish had been done differently or not at all’,” Charles said.
“I’m only too deeply aware of the long history of suffering which Ireland has endured, not just in recent decades but over the years of its history.
“It’s a history that I know has caused much pain and resentment in a world of imperfect human beings where it is always too easy to over-generalise and attribute blame.”
Charles spoke about the peace and reconciliation service in Drumcliffe where WB Yeats is buried, and he recalled a verse by the poet who wrote “and I shall have some peace there, peace comes dropping slowly”.
The Prince added: “As a grandfather myself I pray that his words can apply to all those who have been so hurt and scarred by the troubles of the past so that all of us, all of us who inhabit these Atlantic islands, may leave our grandchildren a lasting legacy of peace, forgiveness and friendship.”