Royal Run In Copenhagen - On The Occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark.

The Royal family of Crown Prince Frederik of Denmark, (L-R) Princess Isabella, Prince Vincent, Princess Josephine, Crown Princess Mary and Prince Christian pose during the Royal Run event in Copenhagen, Denmark, on May 21, 2018. - 70.000 Danes, in the five largest cities of Denmark, take part in the Royal Run event, on the occasion of the Crown Prince's 50th birthday from May 19, 2018.

The Royal family of Crown Prince Frederik of Denmark, (from front row L-R) Princess Isabella, Prince Vincent, Prince Christian, Crown Princess Mary and Princess Josephine take part in the Royal Run event in Copenhagen, Denmark, on May 21, 2018.

The Royal family of Crown Prince Frederik of Denmark, (L-R) Princess Isabella, Prince Vincent, Princess Josephine, Crown Princess Mary and Prince Christian pose during the Royal Run event in Copenhagen, Denmark, on May 21, 2018.

Crown Princess Mary, who married Crown Prince Frederik of Denmark in 2004, looked flawless, sporting bold brows and a touch of blusher and lipstick as she beamed for cameras.

Denmark's Crown Princess Mary (C) looked in good spirits as she joined their four children Prince Christian (R), Princess Isabella (L) and twins Princess Josephine and Prince Vincent at the finish line

The children posed alongside their mother all holding up their medallions dressed in matching t-shirts, with the girls sporting caps like their mother. (L-R) Princess Isabella, Crown Princess Mary, Prince Christian, the royal twins Prince Vincent and Princess Josephine.

Princess Isabella of Denmark during the running event Royal Run on the occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark.

The Royal children (L - R) Princess Isabella, Prince Vincent, Prince Christian and Princess Josephine are ready to on the starting line to begin the 1.6 KM (1 mile) long tour, Royal Run, on the occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark.

Crown Princess Mary of Denmark and daughter Princess Josephine - proudly shows their medals after finishing the 1.6 KM (1 mile) long tour, Royal Run, on the occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark.

Prince Vincent of Denmark during the running event Royal Run on the occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark.

Denmark's Crown Princess Mary wearing her hair tied back under a cap and sporting the official t-shirt, she held up the medal brandishing the numbers 50 - a tribute to her husband whose birthday is on May 26, 2018.

(C) Crown Prince Frederik of Denmark take a photo during the Royal Run on May 21, 2018 in Copenhagen, Denmark.

Crown Prince Frederik of Denmark is seen during the Royal Run on May 21, 2018 in Copenhagen, Denmark. The Royal Run took place in the cities of Aalborg, Aarhus, Esbjerg, Odense and Copenhagen with around 70,000 participants and is part of the 50th birthday celebration for the Crown Prince.

Crown Prince Frederik of Denmark on the starting line of the Royal Run on May 21, 2018 in Copenhagen, Denmark.

Prince Christian of Denmark during the running event Royal Run on the occasion of the 50th birthday of Crown Prince Frederik on May 21, 2018 in Copenhagen, Denmark. Prince Christian did the 1.6 KM (1 mile) run on 7.35 minutes.