It's one of the classic tales of rock n' roll excess in the '70s. But it didn't quite happen as reported. After nearly 40 years, Bianca Jagger says that she did not actually ride into Studio 54 on a white horse to celebrate her 30th birthday in 1977.

Bianca, who was married to Rolling Stones frontmen Mick Jagger at the time, penned a letter to the Financial Times to tell her side of the story. "I would like to set the record straight," she wrote. "Mick Jagger and I walked into Studio 54. [co-owner] Steve Rubell had apparently seen a picture in a magazine of me riding a white horse in Nicaragua and he thought it would be a clever idea to bring a horse to the club as a birthday surprise for me. It was a beautiful white horse that reminded me of mine and I made the foolish decision to get on it for a few minutes. The photographed image went around the world, giving rise to the fable — that I arrived at Studio 54 on a white horse."

She was compelled to write after media mogul Barry Diller mistakenly referenced the event in a recent Financial Times profile. And while it may seem like nitpicking to those of us on the other side of Studio 54's famous velvet rope, for Bianca it's an important distinction. As she continues, "No doubt you will agree with me that it is one thing to, on the spur of the moment, get on a horse in a nightclub, but it is quite another to ride in on one. As an environmentalist and an animal rights defender, I find the insinuation that I would ride a horse into a nightclub offensive."

Jagger, who has won numerous awards for her humanitarian efforts, closes her letter with a bit of wordplay. "Hopefully this letter will finally put this Studio 54 fable — out to pasture."

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