More than a million Second World War documents are to be made available to the public for the first time.
Files from Bletchley Park, the UK's wartime code-breaking headquarters, are to be digitised and put online in a large-scale project expected to take up to five years to complete.
The Bletchley archive currently exists entirely in paper format and much of it is difficult to view, making it inaccessible to the general public. Until now, only limited access to the archive has been granted to academics and educators under strict supervision.
Following an initial digitisation phase lasting around a year the documents, including communication transcripts, memoranda and photographs, will be made available for access using a combination of paid-for and free content.
The project is the result of a collaboration between Hewlett Packard (HP) and the Bletchley Park Trust, which runs Bletchley Park's National Codes Centre and its museum and educational facilities.
Simon Greenish, director of Bletchley Park Trust, said: "This will help preserve and considerably increase access to the historic fragile materials, as well as enable researchers to see and study documents from the code-breaking work that took place during World War Two. There can be few archives which contain material that had such a profound impact on the world at the time and which is still relevant today."