The royal couple have quite the love story, first meeting at a Sydney pub called the Slip Inn when the city hosted the Olympics in 2000.
At the time, Frederik was relaxing with the Danish sailing team, and the pair immediately hit it off. Frederik and Mary Donaldson started to date despite the long distance between Australia and Denmark, and after months of letters and long-distance phone calls, she decided to move from Australia to Denmark to be with her love in December 2001.
On October 8 2003, the couple became officially engaged, with the pair exchanging vows on 14 May 2004.
Since then, the Danish heir to the throne and his wife are parents of four: Frederik's heir Prince Christian, born in 2005; Princess Isabella, born in 2007; and twins Prince Vincent and Princess Josephine, who arrived in 2011. In honour of the couple's anniversary, scroll through some of their most beautiful wedding photos…
WATCH: Crown Prince Frederik and Crown Princess Mary's sweetest moments
When she arrived at Copenhagen Cathedral, the future Princess looked breathtaking in a simple ivory gown by Danish fashion designer Uffe Frank, made of duchesse satin and featuring a 19ft train. The doting mum's wedding look was finished off with a delicate antique lace veil once worn by Crown Princess Margareta of Sweden.
Frederik was a true Prince Charming in his military uniform, while his bride was romantic in her off the shoulder gown as she carried a cascading bouquet that featured roses and Australian eucalyptus flown in especially for the occasion.
Throughout the ceremony, the couple exchanged sweet glances and smiles as the Bishop of Copenhagen, Erik Normann Svendson, told them to "enjoy the day," and to be "happy you have found each other."
Thousands of royal fans from around the globe traveled to Denmark to see the royal wedding. Many of the children waiting on the streets were dressed up as little princes and princesses and waved Danish and Australian flags.
The royal wedding featured a guest list of European royals. Among the first to arrive were Crown Prince Haakon of Norway and his wife Crown Princess Mette-Marit.
Representing the British royal family, the Earl and Countess of Wessex traveled to Copenhagen for the Danish nuptials. Prince Edward's wife looked stunning in a floor length magenta gown accessorized with a shimmering coral shawl.
The then-Crown Prince Felipe of Spain arrived at the cathedral accompanied by his fiancée, news anchor Letizia Ortiz. A week after the Danish nuptials, the Spanish couple had their own royal wedding when they tied the knot in a beautiful ceremony in Madrid.
It was a family affair for the Swedish royals. Foregoing dates, Crown Princess Victoria, Prince Carl-Philip and Princess Madeleine attended the royal wedding together with their parents, King Carl Gustaf and Queen Silvia. The two sisters looked beautiful both opting for brightly colored dresses.
The then Princess Mathilde of Belgium opted for a white flower print dress. The royal's light summery gown brightened up the dark skies that were clouding over Copenhagen.
Parents of the groom Queen Margrethe and Prince Consort Henrik of Denmark were all smiles as they arrived at the cathedral. Before they entered, the couple took a few minutes to wave to well-wishers.
The Prince sadly passed away at the age of 83 in February 2018.
Leaving to great roars from the crowds, the happy couple emerged as husband and wife from the cathedral of Copenhagen. Beaming with joy, the couple climbed into a horse-drawn carriage to make their way to Christian VII’s Palace on Amalienborg Palace Square.
The look of love. The newlyweds could hardly take their eyes of each other as they were taken in an open carriage, accompanied by outriders and an escort of the Royal Danish Guard Hussar Regiment, to their wedding reception.
Upon arriving to the royal palace, the Danish royal family and its newest member, Crown Princess Mary, took to the balcony to wave to royal fans.
The new husband and wife delighted onlookers by sharing a sweet kiss. At the reception, Frederik made an astonishingly romantic speech in which he promised to protect his new wife and make her feel at home in her new country. "The joy and the strength you give me is like the sun in the daytime which, with its radiance, melts all doubts and darkness on earth," he told the 400 guests. "And like the moon at night, you shine with a watchful and delicate beam of gentleness."