Queen Mary of Denmark looks sombre as she lays a wreath with King Frederik at memorial service for fallen Danish soldiers on Flag Day in Copenhagen

Queen Mary of Denmark looked somber as she celebrated Flag Day with her husband, King Frederik, in Copenhagen today.

The 52-year-old royal looked sober during the emotional day, which commemorates people sent on missions by Denmark.

Mary visited the military headquarters in Kastellet, where she and her husband took part in the traditional wreath-laying ceremony for Danish soldiers abroad.

She wore a simple yet chic black dress with a square neckline and quarter-length puff sleeves and accessorized with pink strappy shoes.

Mary paired this with a delicate large pearl necklace and matching stud, earrings, along with a bracelet. She also chose to wear her classic gold Cartier love bracelets.

The mother of four completed her look with a wide-brimmed navy hat, which shielded her face from the sun.

The Queen wore her glossy brown locks loose with a sleek blow-dry and opted for smokey eyeshadow and pink lipstick.

King Frederik, 56, dressed in military regalia, also appeared moved as he laid a wreath. The service was also attended by veterans.

Still, the monarch managed to keep a smile on his face as he sat next to his wife during the ceremony.

September 5th is an official day in Denmark to honor deployed soldiers. During the day, various events and ceremonies take place.

The couple recently said goodbye to their eldest son and heir to the throne, Prince Christian, when he moved to Africa.

The 18-year-old leaves home and heads to East Africa, where he will live until December to work on the farm and ‘learn more deeply’.

The devoted mother of four admitted that it will be very difficult not having her son with her for the next few months.

King Frederik, 56, dressed in military regalia, also appeared moved as he laid a wreath. The service was also attended by veterans

Mary went to the military headquarters Kastellet, where she and her husband took part in the traditional wreath-laying ceremony for Danish soldiers abroad

King Frederik is photographed removing his hat as he takes part in the wreath-laying ceremony with Mary

Mary wore a simple yet chic black dress with a square neckline and quarter length puff sleeves and wore pink strappy heels

Mary paired her ensemble with a delicate oversized pearl necklace and matching earrings, along with a bracelet

Queen Mary of Denmark appeared emotional as she celebrated Flag Day with her husband, King Frederik, in Copenhagen today

The Queen wore her glistening brunette locks loose in a sleek, straight blow-dry and opted for smokey eyeshadow and pink lipstick

The Monarch managed to put a smile on his wife’s face as he sat next to her during the ceremonies

The royal couple were seen sitting side by side as they attended the Flag Day ceremony

September 5 is an official day in Denmark to pay tribute to deployed soldiers and is marked by a number of different events and ceremonies throughout the day

King Frederik is photographed with his wife Queen Mary during Flag Day

“We will miss him immensely… very, very much,” she said at a ceremony in Copenhagen on Wednesday.

She added that both she and King Frederik are excited for him and look forward to hearing about his travels upon his return.

The Danish palace announced that during his visit the young man will work on farms, try out different roles and get to know the community.

He also learns about the natural landscape of Africa and how local people balance work, private life and conservation.

Prince Christian follows in the footsteps of his father and his grandmother Queen Margrethe.

According to a palace spokesman, it is tradition for Danish royals in line for the throne to spend significant time abroad during their youth so that they can learn to appreciate the world more.