Princess Elizabeth showing off her new engagement ring soon after Prince Philip's marriage proposal at Balmoral in 1946
(Picture: PA)With the Platinum Jubilee celebrations a matter of weeks away, most people are looking forward to settling back and enjoying an extra-long Bank Holiday weekend.
However, the BBC is planning on marking the occasion of her seventieth year on the throne in its own way – with a documentary showing previously unseen footage of the Queen.
