Yad Vashem says it has 150 million pages in its archive. USHMM has 100-200 million pages. Both copy from other archives then exchange microfilms and lately, digital files, so there is a lot of overlap between them. However, neither has copied *everything* that would be relevant from other archives. Reading through all of the evidence would require knowing over 20 different languages, so the hypothetical question is to some extent impossible, but I'd think that even just with German and English there would be that many pages to read through, especially since the state-level German archives have a lot of material that hasn't been fully copied to YV and USHMM yet.
The question is how many pages should one read through before enough is enough?
Obviously, some collections are more important than others. The Frankfurt Auschwitz Trial pretrial investigation ran to 88 volumes, and the contents are spelled out
here - well over 1000 interrogations of SS men, bystanders and former prisoners. This is about 18,000 pages of material. The Auschwitz central construction office archive (Zentralbauleitung) runs to about 90,000 pages of contemporary Nazi documents. The most important documents on the crematoria are in a few files of several hundred pages, but important stuff is scattered in all kinds of pages. That is just two collections regarding one camp, Auschwitz, and there are literally hundreds of collections relevant to Auschwitz.
Note that archives won't include published memoirs, although many manuscripts that were later published as memoirs are in different archives. Nobody has an exact count of relevant published memoirs, but I think there are about 2000-3000. These can be short, between 100-200 pages, but some are obviously longer.
For every published memoir, there might be 20-50 unpublished accounts. The total number of witness testimonies of one form or another is certainly over 100,000, across the whole of the Holocaust. Auschwitz predominates for the camps since there were many more Jewish survivors, non-Jewish survivors, bystanders and SS men, so probably 50,000. By contrast, there are maybe 500 witnesses of direct relevance to Belzec, Sobibor, Treblinka and Chelmno, but just counting the survivors and SS (and not including Trawnikis) there are over 1000 separate statements regarding Belzec, Sobibor and Treblinka, as estimated by German historian Sara Berger in her book on these camps.
The fixation on camps obscures the fact that much of the Holocaust unfolded across the whole of Europe. Round-ups and deportations from different parts of Europe have left 10s of millions of pages of material of all kinds. The killings that happened alongside deportations in Poland, or in lieu of deportations in the Soviet Union, left a similar amount of material. Each city and town was investigated at least twice and sometimes many times.
For example, Sonderkommando 4a is well known as the organiser of the Babi Yar massacre; the West German pretrial investigation is about 40,000 pages, and this does not include actual trials. But Police Regiment South also participated, and the pretrial investigation for this unit adds another 14,000 pages. Hans at HC hasn't finished surveying this evidence, despite his
index identifying 62 witnesses already, along with
44 contemporary sources and documents.
Multiply this by many other cities. The West German pretrial investigation into the Riga ghetto is about 20,000 pages long.
