Now the BBC has admitted it may have lost hundreds of rock and pop performances by artists including the Rolling Stones, the Beatles, the Kinks and Bob Dylan.
The corporation has admitted that only 55 out of 3,500 episodes of Top of the Pops made in the 1960s have been stored on tape and that many of the defining moments in pop history may have been lost forever.
The admission came after the BBC'S nostalgia show TOTP2 broadcast a special on the Beatles last month and the producer, Mark Hagen, revealed that not one of the Beatles' appearances on Top of the Pops had been preserved. He said: "I would have loved to use clips of the Beatles on Top of the Pops but unfortunately none of them survives in our archive."
Although older viewers may remember the Beatles performing She Loves You, or Please, Please Me in front of hordes of screaming fans, it seems no-one in the BBC realised the performances were worth saving.
Instead television broadcasts of the Beatles commonly feature their appearance on America's Ed Sullivan Show, singing I Want To Hold Your Hand and a colour film of their performance in New York's Shea Stadium.
Mr Hagen admitted that some of the epoch-making moments in pop history may have been lost forever.
He said: "From around 3,500 1960s performances on the weekly show, the BBC now retains 55, and by no means the 55 you would choose to keep now."
In an effort to track down lost archive material in the past, the BBC launched a nationwide "Treasure Hunt", asking people to hand over home recordings to be remastered.
Several early episodes of Dad's Army were rediscovered, having been rescued by an engineer who found the original reels of film in a skip.
Lost episodes of The Likely Lads and Hancock's Half Hour also re-emerged, along with classic performances from Peter Sellers.
An early recording of Ringo Starr describing his top 12 favourite records was also unearthed, along with early performances from Elton John and Paul Simon.
The BBC's Treasure Hunt website explains: "Forty years ago, few people foresaw the long-term cultural and historical value of television and radio programmes - or their commercial potential. The future significance of popular culture such as comedy or pop music was particularly underestimated.
"Right up until the 1970s, many television and radio broadcasts frequently went out live and unrecorded. For years the only television recording technology was film, and filming was too expensive just to keep programmes in the vaults.
"Video tape was introduced in the mid-1960s, but was still vastly more expensive than today's cheap home technology. It wasn't seen as a permanent store for television programmes. But the tapes could be used again to make other programmes - and many were."