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It has been exactly six decades since Grace Kelly, the darling of Hollywood, married Monaco's Prince Rainier III - and yet the event remains etched in the minds of millions.
Even the royal weddings of Prince Charles to Lady Diana, and Prince William to Kate Middleton haven't dislodged the fairytale moment from history.
And these magical pictures, kept by the Rainier family in Monaco's palace, show exactly why that is.
'It was such an incredible affair, and it's left such a mark on people,' the couple's only son, Prince Albert, told People magazine.
'For us, it was – and you'll have to ask my sisters [Princess Caroline and Princess Stephanie] – for us it was our parents getting married. But what it's meant for Monaco, for people around the world, and, how their story continues to fascinate people, that's something unimaginable.'
Philadelphia-born Kelly had already been dazzling cinemagoers for five years with films such as 'Dial M For Murder' and 'Rear Window' when she headed the U.S. delegation to the Cannes Film Festival in 1955.
While there, she was invited to travel across the French border to the neighboring microstate of Monaco for a photo-shoot with the prince at his palace.
The two met up for the shoot, and afterwards began a secret correspondence. That same year they became engaged, and so began preparations for what became known as 'The Wedding of the Century.'
The Napoleonic Code of Monaco and the Roman Catholic Church required that two ceremonies be held - one civil and one religious - so the entire Palace of Monaco was redecorated for the first ceremony, which was to be followed by a reception for 3,000 Monaco citizens.
Meanwhile, the Saint Nicholas Cathedral had to be prepared for the second, religious, ceremony, which was to be overseen by Monaco's Bishop, Gilles Barthe, and watched on international TV by what was eventually estimated to be 30million people.
MGM, the studio that had seen Kelly through her biggest years as a star, provided two wedding dresses designed by Academy Award-winning Helen Rose, one of which took three weeks to craft.
Invitations were sent out to 700 guests including Aristotle Onassis (later Mr Jackie Kennedy), hotel developer Conrad Hilton and film stars David Niven, Cary Grant, Gloria Swanson and Ava Gardner.
All of this, and the bride was still in America.
The civil ceremony was set for April 18, 1956; the religious ceremony for the following day. But before either of those could happen, Kelly and her sizable entourage had to make the long crossing from America to Monaco.
To get there, they would board the SS Constitution ocean liner and sail for an eight-day voyage to the French Riviera.
And so it was on April 4 that Kelly, along with her family, six bridesmaids, 80 pieces of luggage and a poodle, boarded the ship in New York - along with a horde of reporters and photographers, eager to see history in the making. Some 400 journalists applied to join the crossing, but most were refused.
But even those on the land got a spectacular view: as Kelly stepped onto the ship, a plane owned by Aristotle Onassis flew overhead, spilling red and white carnations on those below.
'The whole Constitution trip was something Mom referred to at times,' Albert told People. 'She'd say it was fun for the wedding party. It really bonded the whole Philadelphia side, her family and friends who came over together on the crossing'
She would also talk about Oliver, her French poodle, he said - a gift from Cary Grant, with whom she had co-starred in Alfred Hitchcock's To Catch A Thief.
Kelly's arrival in Monaco was an even bigger event than her departure, with 1,800 photographers there to capture the moment of their arrival. It had been an exhausting series of events - and the ceremonies hadn't even begun.
'My father said it is exhausting to go through the circumstance, the pageantry, the planning,' Albert told People.
Still, that planning led to one of the most stunning celebrity events of the 20th century, as Monaco entered an eight-day period of festivities leading up to April 17.
And when that day came, the newly renovated palace played host to a huge reception with 40 foreign delegations, outdoor entertainment and a spectacular fireworks display.
The next day the civil ceremony took place in the palace's Throne Room, with Kelly clad in a light pink taffeta dress overlaid with champagne-colored lace - the first of the dresses provided by MGM.
The actual ceremony took just 16 minutes, People reported, but was followed by a full 25 minutes spent listening to the 140 new titles that now belonged to Kelly as Princess of Monaco.
And then the newlywed couple had to repeat the whole thing again for news crews.
The second ceremony took place at the Saint Nicholas Cathedral. As 30million people looked on, Kelly arrived in a fairytale dress comprised of 300 yards of antique Belgian lace and 150 yards of silk, taffeta and tulle.
The veil, itself made of 90 yards of tulle, had been crafted to ensure that Kelly's face would not be obscured from cameras, and her shoes and Juliet cap were decorated with pearls.
It had taken 36 seamstresses three weeks to make the gorgeous clothing, and Kelly did each one of them proud, entering the cathedral looking every bit the princess she now was.
And while his new wife glided serenely under the watchful gaze of millions, Rainier was a little more nervous, and Kelly had to help him slip the ring onto her finger.
The wedding concluded with a traditional offering to St. Dévote, Monaco's patron saint, and a feast of caviar, lobster, champagne and more for 600 people, before the prince and princess boarded the prince's yacht, the Deo Juvante II, for a seven-week honeymoon.
At which point they anchored just off the Monaco shore and promptly fell into a well-earned sleep.
The couple began their honeymoon properly the following day leaving behind memories and images that would last long beyond their own lifetimes.