Also at the Theatre Museum in Covent Garden was Lynn's 31-year-old son Ben , who went against the family tradition and became a pilot.

The archive is more than 41 metres thick

The collection covers the private and working life of Sir Michael Redgrave, including personal correspondence and rare material belong to his father Roy - an Australian silent movie actor - and grandfather.

There are also letters to colleagues such as Sir John Gielgud, Lord Olivier and and Orson Welles, and letters from his university contemporaries such as Anthony Blunt and Guy Burgess - who were both later exposed as KGB agents.

Vanessa Redgrave called it a "wonderful collection" and said she was particularly pleased young people interested in the theatre would be able to view the archive.

She added: "One of the things I like most about the archives are letters from Michael's father, Roy.

Rachel Kempson and Ben Redgrave, with a photo of Sir Michael as King Lear

"They show what the work and conditions for actors were like, although it seems they were just as overworked and underpaid as they are today."

Lynn Redgrave said: "There is some of my father's old theatrical greasepaint in the archive which I remember very well.

"When I used to go and see him backstage I remember the smell and the sight of it, so neatly laid out, very, very well."

Her brother Corin said they had turned down offers from abroad - particularly from the US - to house the archive.

He explained: "We all felt that if it was possible for the archive to stay in Britain, that was by far the best place for it."

It will now take two years to sort and catalogue the archive. When finished, it will be available in exhibitions, the museum's study room and online via the internet.