More than 10,000 candid photographs of the royal family, taken by the infamous Ray Bellisario, are coming to the UK's Omega Auctions in London on October 10.
Bellisario, who is often regarded as the first paparazzo, has consigned the transparencies and negatives from his own private collection.
They include images of Prince Charles water-skiing in 1970, the Queen dancing the twist in 1962, and the Queen strolling with the disgraced Duke of Windsor in 1965.
Bellisario's continued presence at the royal family's private get-togethers from the 1950s to the 1970s made him unpopular with the Windsors, prompting Princess Margaret to once exclaim: "That bloody Bellisario!" and Prince Philip to suggest locking him in the Tower of London.
Each will be sold with its copyright to raise money for Reach For Rights, the charity Bellisario founded last year to provide free legal help.
The collection, which will also include a further 10,000 photographs of key public figures, including British prime ministers and Hollywood actors, will be split into 300 to 500 lots, with the auction expected to make between £500,000 ($774,828) and £1m ($1.6m).
"Some of the photographs are exclusive beyond challenge," comments Bellisario.
"Whoever acquires the 'Ray Bellisario Collection' is buying history. They created controversy when they were obtained and there is no doubt that they will prove controversial not only when they are purchased but shall in the future."
Auctioneer Paul Fairweather is confident the collection will sell well. "This is a remarkable collection and we expect there will be significant interest not only in the UK but worldwide.
"It is such a unique collection with nothing ever having come up for sale previously to compare it to."
You can view our collection of royal family autographs for sale here.