Nazi Germany's Holocaust claimed the lives of more than six million mainly Jewish victims, killed systematically through gas chambers, mass shootings and other brutal methods.
Germany is often distinguished for the open way it now reflects upon its past, with numerous museums, memorials and art projects across the country, aimed at reminding the country of the history.
Here's a look at how Germany is honouring the day this year, as well as some of the history.
History of the day
Germany has gone through different phases of self-examination in coming to terms with Adolf Hitler's regime, and it wasn't until 40 years after the end of the Second World War that Germany named an official day to remember victims of the Nazis' genocide.
The 1968 student movement in West Germany during the Cold War played a large part in bringing discussions of the Nazi history to the forefront of debates.
In 1996, German President Roman Herzog - who died earlier this month - first declared January 27th as the official day of remembrance, marking the 1945 liberation of the Auschwitz concentration camp.
It was a time of deep reflection for the country, with the official remembrance day declaration preceded the year before - on the 50th anniversary of Auschwitz's liberation - by numerous speeches, television documentary specials and reflective newspaper think pieces.
"The darkest and most awful chapter in German history was written at Auschwitz," then Chancellor Helmut Kohl said in 1995. "Above all, Auschwitz symbolizes the racial madness that lay at the heart of National Socialism and the genocide of European Jews, the cold planning and criminal execution of which is without parallel in history."
On that first memorial day, politicians and former concentration camp prisoners laid wreaths at sites across the country, but some members of the Central Council of Jews in Germany criticized the ceremonies as insufficient.
About a decade later in 2005, the United Nations also declared the day as the International Holocaust Remembrance Day.
Memorials on Friday
The Berlin memorial to Sinti and Roma victims of the Nazis. Photo: DPA.
Concentration camp sites around Germany and elsewhere are holding memorials on Friday, including at the site of the former Auschwitz camp in Poland - where more than 1.1 million people were killed.
The Bavarian state parliament is a guest at Prague's ceremony to remember the victims in the Czech camp of Theresienstadt. During Nazi times, more than 81,000 Jews were deported from the “Protectorate of Bohemia and Moravia” under Hitler's rule. Only around 10,500 survived the Holocaust.
The German parliament (Bundestag) is also observing an hour of reflecting on the victims of the Nazi regime. Chancellor Angela Merkel attended the ceremony in the Bundestag, at which parliament speaker Norbert Lammert made a speech about the Nazis' often forgotten “euthanasia” programme, which killed 300,000 ill and disabled people.
Lammert said the programme was the first to use gas to murder those considered "unworthy of living" and served as a "trial run for the Holocaust".
"It became the model for the mass murder that would follow in the Nazi extermination camps," he said.
The euphemistically-named 'euthanasia programme' involved doctors and scientists exterminating the sick, physically and mentally disabled, those with learning disabilities, and those considered social “misfits”.
Between January 1940 and August 1941, doctors systematically gassed more than 70,000 people at six sites in German-controlled territory, until public outrage forced them to end the overt killing.
But tens of thousands more died across Europe until the war's end in 1945, through starvation, neglect, or deliberate overdoses administered by caregivers.
Many also underwent cruel medical experiments and forced sterilizations because of their supposed genetic inferiority.
In Friday's ceremony, an actor with Down's syndrome read out a letter from one of the victims, Ernst Putzki, who wrote to his mother in 1943 describing the inhumane conditions at the institution where he was being held in Weilmuenster, western Germany.
"Death from starvation is hard on our heels and no one knows who will be next," he wrote.
"Before, the people here were killed more quickly and their bodies were taken for burning at dawn. But this was met with resistance from the locals.
"So now we are simply left to starve."
Putzki died in January 1945, officially of pneumonia.
On his last day as foreign minister - before he is expected to become President - Frank-Walter Steinmeier also expressed his thoughts about the day of remembrance.
“We cannot change or undo what happened. For us, though, it is our mission and duty to remember the collapse of civilization that was the Holocaust, as well as to commemorate the victims and the responsibility that we take on today.”
In a world “that may seem uncertain, restless and without order,” history is a lesson, warning and incentive, Steinmeier continued.
“Remembrance has no end, and also should not have one.”
But not everyone has been allowed to participate in the memorials as they please. Far-right AfD politician Björn Höcke gave a speech last week condemning the way Germany remembers its history, calling the Berlin Holocaust memorial a “memorial of shame” and saying that a former president who encouraged the country to take responsibility for the Nazis' crimes had spoken “against his own people”.
Höcke was uninvited from a memorial service at Buchenwald concentration camp, and was also kicked out of his Thuringia state parliament's commemoration hour.
The politician's statements were widely criticized by Jewish groups and other parties as “anti-Semitic” and an attempt to “re-write history”.
Even his party's leader, Frauke Petry, responded to his comments by calling Höcke a “burden” on the party.