Seventy-five years on from the Nuremberg Trials, the last surviving prosecutor of the Nazi war criminals behind some of history's worst crimes is 100-years-old and still spreading a message to younger generations about the scourge of conflict and repression.
Benjamin Ferencz was 25 and a US soldier when, in the last days of World War Two, he was assigned to collect evidence about the war crimes committed by Germany under Adolf Hitler.
Later, Ferencz became a prosecutor at the US military tribunal in Nuremberg, southern Germany, securing the convictions of 22 members of the Einsatzgruppen - paramilitary death squads who slaughtered upwards of a million people, most of them Jews, across occupied Europe.
"There are very few people who have seen what I have seen," he said from his home in Delray Beach, Florida.
"My job was to get into the concentration camps as they were being liberated, with the dead bodies all over the floor and with people waiting to be burned because the crematorium was so overcrowded."
The trials are today seen as the forerunners of tribunals like the International Criminal Court (ICC) in The Hague, which has prosecuted politicians and soldiers for their crimes against humanity, albeit with mixed results.
Ferencz campaigned for decades for the ICC to be established, delivering a closing prosecution statement at the conclusion of its historic first case, against the Congolese warlord Thomas Lubanga, in 2012.
"Take your case to a fair court and have them decide what's right and what's wrong," he said on Wednesday. "Now you save yourself killing a lot of innocent people."
The courtroom in Nuremberg has been preserved and still draws many visitors to see the seat where defendants like Air Marshal Hermann Goering heard their death sentences.
"There is huge interest," Axel Fischer, curator of the museum, said.