Israeli President Isaac Herzog visited the Bergen-Belsen Nazi concentration camp on Tuesday, retracing the footsteps of his father who helped liberate the site as a British army officer in 1945.
Recounting Chaim Herzog's first moments at the camp -- Isaac's father and former Israeli president -- the leader said he "stood on a wooden box, shouting in Yiddish before hundreds of skeletons".
"'Jews, Jews, are there still Jews alive? Are there still Jews alive on this earth?'" Herzog recalled his father saying.
The camp is one of the most notorious of World War II, where over 50,000 people died, including the diarist Anne Frank.
In 1945, it was covered with barracks that the British army quickly burned down to stop diseases from spreading.
Today, there are huge mass graves covered with grass, on which small stones are placed as tributes for the dead.
Standing next to a stone brought from Jerusalem by Chaim Herzog in 1987 when he became the first Israeli president to visit Germany after World War II, his son Isaac urged the two countries to keep up the fight against anti-Semitism.
"It's our duty in the name of the past," he said.
Germany's President Frank-Walter Steinmeier, who accompanied Herzog on Tuesday's visit, said it took a long time for Germans to realise that they too were liberated at the end of the war.
Paying tribute to Chaim Herzog, he said Germany must "never forget the Holocaust".
- 'Hell on earth' -
Bergen-Belsen was one of the first concentration camps to be liberated by the Western Allies, who arrived to find it riddled with disease and about 10,000 unburied corpses.
Those held at the camp included Jews as well as prisoners of war, homosexuals and political opponents.
In a speech earlier Tuesday at the Bundestag, Herzog said he would "never forget how (his father) described to me the horrors" he witnessed at the camp.
"The stench. The human skeletons in striped pyjamas, the piles of corpses, the destruction, the hell on earth."
During Chaim Herzog's trip back in 1987, he said: "I bring with me neither forgiveness nor forgetfulness. The only ones who can forgive are the dead; the living have no right to forget."
Isaac Herzog said he brought that same bequest to Germany on the current visit, "etched on my heart".
At the site now dotted with pine, oak and birch trees, five survivors -- Swedish national Jovan Rajs, Israelis No'omi Rinat and Jochevet Ritz-Olewski, American Menachem Rosensaft and German Albrecht Weinberg -- also joined the ceremony.
Weinberg, now 97, was 20 years old when Bergen-Belsen was liberated.
He had spent 60 years in the United States before returning to his city of origin, Leer, in northern Germany, which invited him back and named a school after him.
Weinberg said he goes to the school regularly to recount his experiences to pupils "who cannot understand how something like that could happen".
"I am one of the last survivors," he told AFP.
"As long as I can, I will continue to speak about what happened."