Those who were there and, against all the odds, managed to live to tell it as it was have provided a vital archive through video, audio and written testimony.

Equally though, those who have spoken from the grave offer an entirely and somewhat eerie perspective.

The Ringelblum Archive is such a resource.

Comprising two milk churns and 10 crates, they were discovered in the ruins of the Warsaw Ghetto and contain documents buried by a group known as Oyneg Shabbos or Oneg Shabbat today.

The group, led by Jewish historian Dr Emanuel Ringelblum, included historians, writers, rabbis and social workers, who methodically collected documents and testimonies to ensure that if they did not survive, the truth would be known.

The material they collected, from September 1939 to January 1943, included essays, diaries, drawings and posters describing their ordeal in the Ghetto.

Some 6,000 documents (about 35,000 pages) are today at the Jewish Historical Institute in Warsaw.

A third milk churn has yet to be located and is believed to be buried beneath what is today the Chinese embassy.

A search in 2005, however, failed to locate the archive.

Only three members of the Oyneg Shabbos group survived.

Ringelblum escaped the ghetto. but in 1944 he and his family were executed.

Documenting other ghettos was less successful.

Nothing exists from Krakow, although there is an important archive of the Lodz ghetto, including photographs taken by the leadership.

Concentration camp inmates were equally concerned that their testimony be known if they did not survive.

Scrolls of letters were unearthed around Birkenau, documenting what inmates experienced and what they had seen.

Sharon Kangisser Cohen, director of the Diana and Eli Zborowski Center for the Study of the Aftermath of the Holocaust at Yad Vashem, said: “The feeling was, ‘even if we risk our lives, the story has to be told’.

“Testimony is the narrative of survival.”

With survivor testimony, since this was sometimes recorded decades after the event, there was always the issue of accuracy; of memories playing tricks.

There is the issue, too, of the veracity of recollections of those who were young children at the time.

Yad Vashem’s deportations’ database is another vital resource which, as with all the memorial’s material online, is free to access.

To date, Yad Vashem has data from 1,260 deportations but believes there could be as many as 3,000 lists or many more.

Via the website, there are links to testimonies, too.

This online guide includes most of the transports that originated from cities in central, western and southern European countries between 1939 and 1945.

It is part of a large-scale research project ‘Transports to Extinction’, that records, and describes in detail, the deportations of Jews to ghettos, camps, and death camps during the Holocaust.

The guide provides basic information about the transports.

Some of the items that appear on the list are linked to the projects website, where additional information and documentation are presented.

Included are deportations from Austria, Belgium, Czechoslovakia, France, Germany, Greece, Italy, Luxembourg, Poland and the Netherlands.

The fact that at that time Jews were marched through the cities shows that the indigenous population saw in broad daylight what was happening and were probably aware of the Jews’ destiny.

This raises the question of complicity of locals in the Holocaust, and the fate of six millions European Jews.

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