The royal, 48, took to Instagram on Wednesday to share a close-up showing her leaning on her husband's shoulder, both smiling at the camera. She captioned the personal image simply with: "20 years [purple heart emoji]."
The Norwegian royal family's official Instagram account also shared some stunning photos from Crown Prince Haakon and Crown Princess Mette-Marit's wedding day, as well as images of the couple with their children and on their public engagements.
WATCH: Relive the love story between Crown Princess Mette-Marit and Crown Prince Haakon
The pair tied the knot at Oslo Cathedral on 25 August 2001, with the bride wearing a white silk crepe gown that was designed by Norwegian wedding dress designer Ove Harder Finseth. She accessorised with a diamond bandeau-style tiara, made in 1910, which was a gift from her new in-laws, King Harald V and Queen Sonja.
Crown Princess Mette-Marit marked the couple's 20th wedding anniversary
Crown Prince Haakon and Crown Princess Mette-Marit welcomed their first child, Princess Ingrid Alexandra, on 21 January 2004, and their son, Prince Sverre Magnus, on 3 December 2005. The crown princess also has a 24-year-old son, Marius Borg Høiby, from a previous relationship. Marius holds no title and is not part of Norway's royal family's line of succession.
The happy couple on their wedding day in 2001
It added that her parents and her younger brother, Prince Sverre Magnus, 15, have been tested, but were not positive for the virus.
As a result of their exposure to coronavirus, Crown Prince Haakon and Crown Princess Mette-Marit have postponed the 20th anniversary celebrations of the Crown Prince Couple's Foundation that were due to take place on Wednesday.
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