Rare photo of Princess Anne's waist-length hair will make you double take

Princess Anne's hair has famously been swept up into a bouffant, ballerina-like chignon for the 55 years she has been a working royal. The late Queen Elizabeth II's daughter rarely deviates from the sleek and elegant hairstyle, which she has been rocking ever since she was a teenager.

While the infamous beehive has dipped in and out of style through the decades, the Princess Royal has remained its most loyal fan. She even had time to pin it up before leaving the hospital after giving birth to her children, Peter and Zara.

"It's like armour," Claudia Harrison (who plays Princess Anne in "The Crown") told Marie Claire, who added that Anne's loyalty to her perfectly-executed 'do is parallel with her unmatched work ethic and undisputed reputation as the hardest working royal.

It's hard to picture the 72-year-old royal's hair in anything other than the regal 1960s inspired up-do, but one rare photograph from the archives shows the surprising length of Princess Anne's Rapunzel-like mane.

Back in 1982, a then 33-year-old Anne was pictured leaving the 2UE building in North Sydney after being interviewed by radio presenter John Laws.

The Princess Royal styled her hair in an elegant half-up, half-down style. While the top of her hair was pinned into its usual, voluminous beehive quiff, the back revealed a surprisingly luscious mane that fell to just above her waist.

The photograph marks one of the only times the royal was photographed letting her brunette tresses fall naturally - and just look at that length!

PRINCESS ANNE'S STYLE FILE

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• Princess Anne's unroyal backless dress in unearthed photos will make you double take

It's not the first time unearthed photographs from the Princess Royal's style file have documented her glamorous style and trailblazing fashion moments. While Princess Anne's modest style may now reflect her senior royal position, the mother-of-two was once the monarchy's It-girl; rocking knee-high boots, sporting zany 70s florals and even wearing glittering tiaras before she was officially permitted to.

Throwback photographs taken from the royal's meeting with King Constantine of Greece in London back in the 1980s show her donning a beautiful blue silk dress with a seriously daring halter neckline.

While off-the-shoulder looks aren't forbidden in the royal rule book, they certainly would have raised eyebrows at the time, especially when worn by the Queen's daughter!