A fairytale frock and a clutch of royals is probably all Prince Harry's wedding will have in common with the monumental nuptials of his parents, Prince Charles and Lady Diana Spencer.
The "wedding of the century" in 1981 drew a global TV audience of 750 million, with two million people turning out on the streets of London to cheer the future king and his young bride.
People gasped as Diana stepped out of her glass carriage onto the red carpet lining the steps of St Paul's, her father Earl Spencer proudly by her side.
Her stunning ivory silk taffeta and antique lace gown with its 7.6m train, puffy sleeves and frilly neckline had been carefully kept under wraps until that moment despite intense media interest in the lead up to the wedding.
Inside St Paul's Cathedral waiting to witness the historic event were 3500 guests, including the biggest gathering of European crowned heads and foreign royals.
At the time, and for all the world knew, Diana was a true fairytale princess with a charmed life ahead of her - an aristocratic young woman of just 20 marrying the most eligible bachelor on the planet.
Robert Runcie, the archbishop of Canterbury who presided over the couple's wedding, told the congregation: "Here is the stuff of which fairytales are made".
India Hicks, who as a 13-year-old was one of Diana's five bridesmaids, remembers the historic day as one when two families came together and how "everybody was just wanting it (the marriage) to work and just believing in it".
"That wedding is so weighted in history for all sorts of reasons, the enormity of it, the fairytale-ness of it, nobody knew what was going on underneath," she told E!News in March this year.
"It was so much bigger than I imagined it to be. When I look back, and I think, 'Oh my God' my head (is on) a piece of a jigsaw puzzle now.' That's kind of weird. I rode in a horse-drawn golden carriage; my life is so different now. It was amazing but, no, I didn't appreciate the enormity of the occasion back then."
Prince Harry is taking a dramatically different approach for his wedding to American actress Meghan Markle on Saturday.
The couple have opted for the much more low key venue of St George's Chapel at Windsor Castle, where just 600 guests will witness them exchange their vows.
And while his nearest and dearest royal relatives, including the Queen, will watch on the rest of the pews won't be filled with heads of state and politicians.
Those lucky enough to score an invite also don't have to worry about what to buy as a gift as Harry and Meghan have asked for donations to be made to seven specific charities instead.
By contrast, 6000 presents were sent to Charles and Diana, including 20 handcrafted silver platters presented in a box of made from Australian blackwood.
But by choosing to have their wedding at Windsor, Harry and Meghan will miss out on carrying on the tradition started by his parents - and adopted by brother Prince William and Kate Middleton when they wed in 2011 - of sharing a romantic wedding day kiss on the balcony of Buckingham Palace.
Kensington Palace has been at pains to stress that the day "will be a moment of fun and joy that will reflect the characters and values of the bride and groom".
But as hard as Harry's tries make his wedding as different as possible to that of his parents, memories of Charles and Diana's iconic event will doubtlessly come flooding back for some.
"There's no doubt Charles and Diana's wedding was one of the biggest of all times," royal commentator Richard Fitzwilliams told AAP.
"But it was a fairytale turned nightmare.
"Harry and Meghan's wedding is seen as being indicative of the enormous changes that have taken place within the royal family.
"The fact that the royal family is so inclusive, the fact that Meghan is a divorcee, the fact that she is biracial, the fact she's a former actress and she's going to continue to be an activist."
While everything appeared joyous on Diana's wedding day, years later she sensationally revealed a troubling picture of what was going on behind the scenes.
In Andrew Morton's biography of the Princess of Wales, Diana Her True Story, she told of how she was bulimic, shed plenty of tears and argued with Charles in the days before the wedding, mainly about his continuing attachment to Camilla Parker Bowles.
"So, walking down the aisle I spotted Camilla, pale grey veiled pillbox hat, saw it all, her son Tom standing on a chair," she told Morton.
"Got out (of St Paul's), was a wonderful feeling, everybody hurraying, everybody happy because they thought we were happy and there was the big question mark in my mind.
"I realised I had taken on an enormous role but had no idea what I was going into - but no idea."
Unlike newlyweds in fairytales, Charles and Diana didn't live happily ever after.
While they celebrated the birth of their sons, William in 1982 and Harry two years later, they finalised their divorce in 1996, just 12 months before Diana died in a Paris car crash.
