Princess Mary shares selfie as she plays tourist during day trip with husband Prince Frederik

Crown Princess Mary has shared a selfie taken during a day trip with husband Crown Prince Frederik.

Mary, 49, took the photo from the top of an observation tower in the town of Haslev, around 60km south-west of Copenhagen.

Unlike members of the British royal family, particularly Prince William and Prince Harry, Mary isn't against taking a selfie or having a selfie with royal fans.

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Princess Mary and Prince Frederik climbed the Forrest Tower, a 45m treehouse-like structure that takes tourists to a viewing platform 140m above sea level with a view of the surrounding forest and fields.

It is nestled within the grounds of the Gisselfeld Kloster, one of Denmark's oldest and best-preserved Renaissance castles.

Mary and Frederik posed for photos at the very top of the tower, looking out to see their home, Amalienborg Castle, which can be seen in the distance on a clear day.

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The Crown Prince couple visited Haslev to mark 150 years since the railway came to town, opening it up to tourism and trade.

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Their children Prince Christian, 15, Princess Isabella, 14, and twins Prince Vincent and Princess Josephine, 10, did not join their mum and dad for the day trip.

The tour was postponed by a year due to the coronavirus pandemic.

Denmark's Queen Margrethe II is also away, embarking on a long-awaited visit to Greenland which was also pushed back due to the pandemic.

For Mary's outing overnight, she wore a reversible coat by Massimo Dutti, a piece she has worn many times over the years.

READ MORE: Princess Mary is urging us to 'take responsibility' when buying clothes

In the past few months alone for royal engagements, Mary has chosen older outfits from her extensive wardrobe instead of buying new pieces, with some of her items dating back at least 10 years.

Late last week Mary gave the opening address at the 2021 Copenhagen Fashion Summit (CFS+), where she called on consumers everywhere to "take responsibility" when choosing what clothing they buy to reduce the amount of waste on the environment.