The royals touched down at the small south-western airport of Pau-Pyrenees last week.
Local reports say that the Cambridges were visiting friends and relatives in the area.
France has always been a popular holiday destination for Prince William and Kate. They took their first holiday as a family of four, with George and Charlotte, to the French Alps earlier this year.
This year will be the first time that Prince Carl Philip and Princess Sofia of Sweden take a summer holiday as a family of three with baby Alexander.
With the sun, good atmosphere, tranquillity and anonymity, the couple set sail for Barcelona (pictured) in July, for their first getaway of the season.
According to the Swedish press the family stayed in the exclusive W Hotel, located on the beachfront along the Barceloneta promenade.
This isn't the first time that the couple have visited Spain. For several years the pair travelled to Ibiza with friends to take advantage of the beautiful beaches, excellent restaurants and world-famous nightlife.
Crown Princess Victoria and Crown Prince Daniel of Sweden began their summer in Olän. Every year the Swedish royals meet there to celebrate Victoria's birthday on 14 July.
After spending the first few weeks in their summer palace, the family like to travel to the beach, often choosing Saint Tropez (pictured) as their destination of choice.
Victoria, Daniel and their two children, Estelle, four, and newborn baby boy Oscar, stay in the village of Saint Maxime at a house that the Swedish princess inherited from her Uncle Bertie.
The family are often spotted trying out local delicacies, taking in the wonderful scenery along the French Riviera and spending sun-kissed evenings eating out with friends.
King Willem-Alexander and Queen Maxima of the Netherlands have their bags packed and they're almost ready to go.
Although the Dutch royal family never reveal the destination of their summer holidays, in the past they have favoured Greece, especially the town of Kranidi (pictured), where they stay in a stunning summer residence.
The king and queen have also been spotted enjoying a romantic summer holiday in Italy before, where they were seen mixing with other tourists as they ambled around the historic cities.
For the first time ever the king's working place, Noordeinde Palace in The Hague, has been opened to members of the public while the monarch is away on holiday.
For their summer holiday, Crown Prince Frederik and Crown Princess Mary of Denmark headed off to the East coast of Jutland, the Danish countryside that borders Germany.
Following tradition, the Crown Princes and their four children took up residence at Gråsten Castle, for the first part of their summer holidays.
During their time in the beautiful countryside, the family take part in many sporting activities including horse rides and cycling trips with their Border Collie, Ziggy.
For their final few days of summer the family will relocate to their Aarhus residence where they stay with Queen Margrethe and Prince Henrik.
But before then, Frederik and Mary will travel to Rio, Brazil for the upcoming Olympics where they will cheer on Denmark's national team and attend the opening ceremony.
Prince Joachim and Princess Marie of Denmark opted for a long-haul adventure this summer, travelling to the border of Brazil and Argentina to see the world-famous Iguazu Falls.
The couple brought their two children Prince Henrik and Princess Athena, and Joachim's two sons from his first marriage, Prince Nikolai and Prince Felix.
A photo was posted on the Danish royal family's Instagram page, showing the group-of-six posing in front of the magnificent waterfalls, the largest waterfalls system in the world.
Joachim and Marie are in South America ahead of the Rio Olympics, where they will attend the opening ceremony and other sporting fixtures.
Every season Marivent Palace in Majorca hosts the Spanish royal family and their friends.
King Felipe, Queen Letizia and their daughters Princesses Leonor and Sofia, who also visit the island at Easter, are often seen taking in the local sights and the beautiful surroundings that the island has to offer.
As a family of avid sailors, King Felipe and his two daughters also head down to the port to watch the Copa del Rey yachting competition that takes place every year.
The family arrived on the island last weekend and kicked off their summer holiday with a big reunion at their favourite restaurant Flanigan, located on the Portals Nous marina.
Felipe, Letizia, Leonor and Sofia were joined by King Juan Carlos and Queen Sofia, and Infanta Elena and her two children Felipe and Victoria.