Her voice choking with emotion, the President, Mrs McAleese, said she had never been to such a place before but her heart was now full of the souls whose lives were wasted.
She and Dr Martin McAleese were at Majdanek concentration camp outside Lublin, in eastern Poland, yesterday.
It was the last event of their two-day state visit and they travelled there by the same route as many of the former inmates - from Lublin Castle, then a Nazi prison. Three hundred thousand men, women and children passed through Majdanek and 235,000, half of them Jewish, died by gassing, shooting, beating or malnutrition.
Today it is preserved as a museum. It is a plain of overgrown green fields crisscrossed by double rows of barbed wire and dotted with high observation posts and old wooden prison huts. Two huge memorials dominate the landscape, the mausoleum containing the ashes of the dead, and a modern stone sculpture at the entrance.
The central complex housing the gas chamber, crematorium, where up to 100 corpses a day were burned, and dissecting room still stands and the Irish party viewed it in all its horror. Mrs McAleese was visibly moved.
Holding back tears, she said she found it hard to express her feelings, "but I feel I need to be reminded that 60 years ago at a time when we thought of ourselves as a civilised people we were capable of extreme evil." It was a story of Europe "and we are not proud of anything that happened here but I hope that out of this we will carve a better future so that children will never know such evil visited upon them again."
The Irish party was told that in one day in November 1943, 18,400 people were shot at the camp. The Nazis called it "the harvest festival". The last execution took place on July 21st, 1944, the day before Majdanek was liberated by the Red Army.