Princess Mette-Marit is the picture of summer in a chic floral crown

Princess Mette-Marit of Norway chose to wear a pretty garland on her head for a big celebration on Thursday (June 23), trading her tiara for a floral 'crown.' The future queen of Norway celebrated King Harald and Queen Sonja's 25th anniversary on the throne with the rest of the royal family.

Mette-Marit made a pretty appearance on the Stiftsgården palace balcony in Trondheim city, giving onlookers summer vibes with her boho look.

She wore a chic lilac dress that she paired with nude heels and a straw clutch and had her blonde hair tousled into loose waves.

TAP TO VIEW GALLERYNorweigen royal family on balcony The Norwegian royal family were marking King Harald and Queen Sonja's 25th coronation anniversary

Crown Prince Haakon's wife stood alongside her husband, the couple's daughter Princess Ingrid, 12, and their ten-year-old son Prince Sverre. Mette-Marit's elder son Marius, 19, from her previous relationship, also joined the royals on the balcony.

It was a big day to mark Harald and Sonja's coronation. Completing the royal gathering was Princess Märtha Louise and her three daughters Maud, Leah and Emma, who all wore floral crowns.

The royals started the day at the Ravnkloa fish market where they enjoyed "breakfast with the people". They mingled with locals and inspected the fresh catch of the day, before attending a church service.

Princess Mette-Marit waves away on a boat The female royal family members sported pretty floral crowns

A garden party was then held at the Stiftsgården royal residence, where King Harald gave a speech.

"Trondheim is a very special place for us," he said. "Not just for the Queen and myself, but because of its long tradition and deep roots for the entire Norwegian monarchy."

He made reference to their earlier church service, saying: "Nidaros Cathedral shows us how history is woven into our lives and it places us in the long line of people and events that together comprise our nation's history."

Princess Mette-Marit Mette-Marit wore a lace summery dress

To mark the king and queen's coronation anniversary, a new portrait was released showing the three generations of the family – King Harald, Crown Prince Haakon and Princess Ingrid.

The portrait was taken in front of the Norwegian royal regalia, in the same spot where Harald and Haakon were photographed ten years previously.

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