Princess Anne announced her engagement to her first husband, Captain Mark Phillips on 29 May 1973. An official engagement portrait shot by renowned photographer Norman Parkinson was released at the time, showing the Princess Royal's exquisite gown, but did you know she was actually wearing two?
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The main dress seen in the image was designed by Zandra Rhodes, but it was reportedly so sheer that she was required to wear a second style beneath it for more coverage.
Mark, who was a lieutenant in the 1st Queen's Dragoon Guards, proposed to his bride-to-be with a sapphire and diamond engagement ring designed by Garrard Jewellers.
Princess Anne and Captain Mark Phillips' engagement portrait
They tied the knot less than six months later, on 14 November, at Westminster Abbey, where Princess Anne's mother and father had also married 26 years earlier.
The ceremony was watched by an audience of approximately 500million TV viewers around the world, while hundreds of fans also took to the streets of London to celebrate Princess Anne and Mark's big day.
Anne arrived at the venue in a horse-drawn carriage, which was escorted by her father, the Duke of Edinburgh. Her bridesmaid was nine-year-old Lady Armstrong Jones, the daughter of her aunt, Princess Margaret, while Anne's youngest brother, nine-year-old Prince Edward acted as page boy.
Princess Anne and then-husband Captain Mark Phillips on their wedding day
Princess Anne's wedding dress was just as beautiful as her engagement gown, too. She opted for a Tudor-style silk gown with a high collar and medieval sleeves, designed by Maureen Baker, a seamstress who had previously worked as chief designer of ready-to-wear label Susan Small.
Princess Anne accessorised with her grandmother's diamond tiara and a veil, while she styled her hair in a parted up-do and beehive. Captain Mark Phillips, meanwhile, wore the full scarlet and blue uniform of his regiment at the time.
Princess Anne and Mark Phillips then announced their separation in August 1989, before divorcing in 1992. Anne went on to marry naval officer Commander Timothy Laurence in 1992, and they are still together today.
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