She recently spent nearly a month in her native Australia - sunning herself on the beach, surfing in the ocean and watching her children play in the sunshine.

So it would have been a very abrupt return to reality for Crown Princess Mary when she arrived home in the depths of Danish winter.

The princess, 43, was pictured bundled up against the frigid cold to cycle her twins Prince Vincent and Princess Josephine to school.

Brrrr-aving the cold: Crown Princess Mary was spotted cycling her children Vincent and Josephine to school in the snow in Copenhagen

Back to reality: The 43-year-old royal was pictured hiding her face in a scarf and bundled up with a fur-lined jacket, beanie and gloves as she rode through Amalienborg Palace

Winter wonderland: Twins Vincent and Josephine, who turned five the day of their outing, kept warm with a blanket over their legs, while pet dog Ziggy ran alongside them

In pictures taken on January 8 - just a week after the royal family's return to Copenhagen - the mother-of-four can be seen hiding her face in a scarf as she rode through the snow.

Wearing a thick, fur-lined jacket, a beanie, gloves and boots, Mary cycled behind her husband Prince Frederik, who was also dressed for the frosty conditions.

Their five-year-old children - who celebrated their birthday on the day these family snaps were taken - can be seen cringing against the cold wind as they sat in the front of the cargo bike with a blanket draped over their knees.

Family outing: Crown Princes Frederik led the way (left), while royal bodyguards followed at a distance

Depths of Danish winter: While the family enjoyed sunny climes in Australia, it was back to single digit temperatures and snow in Copenhagen

Wrap up warm: Frederik wore a bright blue jacket and red jeans for the short bike ride (left), while Mary and the twins matched in fur-lined coats (right)

The adorable youngsters wore similar fur-lined winter jackets to their mother, and protected their heads from the cold with knitted hoods.

The family's beloved border collie, Ziggy, ran alongside them, while bodyguards trailed behind.

It is not an unusual sight for Copenhagen locals to spot their Crown Princess on her Nihola cargo bike, cycling her youngest children from Amalienborg Palace to their school - but rarely in such wintry conditions.

Summer Down Under: Mary spent December in Australia, visiting Perth, the Gold Coast and Byron Bay (pictured)

Back to work: After a brief hiatus when they returned to Denmark in January, Mary has been pictured at a number of events over the past week, including the Women's Board Awards (pictured)

Over the summer, the stylish royal was even caught on camera riding her bike through the city wearing a tight leather pencil skirt.

Mary, who will celebrate her 44th birthday on Friday, has returned to royal duties following her Christmas holiday.