Kate Middleton and Prince William are visiting Sweden on January 30, and are touring the Swedish capital of Stockholm.
The Duke and Duchess of Cambridge will then move on to Norway.
The parents of two, Prince George, four, and Princess Charlotte, two, are meeting the royal families of both the northerly countries.
Kate and William are not staying with the royals and will instead be hosted in the Residence of the British Ambassador to Sweden.
However, they have been invited to various royal residences and will dine with a number of Swedish royals.
Pregnant Kate and William are set to dine with King Carl XVI Gustaf, 72, and Queen Silvia, 74, at the Royal Palace in Stockholm.
They will also be joined by Crown Princess Victoria, 40, and husband Prince Daniel, Duke of Västergötland, 44.
Victoria is the eldest of King Gustaf’s children and she married Daniel, who was a personal trainer, in 2010. She has two children Princess Estelle, five, and Prince Oscar, one.
Kate and William will he hosted the next day at Haga Palace for tea, where Crown Princess Victoria and husband Prince Daniel live.
It is not clear whether Kate and William will officially meet for photo calls with Princess Sofia and Prince Carl Philip – but they may well meet behind the scenes.
Prince Carl Philip, 38, is the second eldest child of the Swedish royal family.
He married his wife Princess Sofia, 33, a former glamour model and reality TV contestant, in 2015 and the pair have had two children, Prince Alexander and Prince Gabriel.
The youngest of King Gustaf’s children is Princess Madeline, who would have something with both Kate Middleton and William, as she studied Art History at University.
However, it was announced that Kate and William will not meet Princess Madeleine on their visit.
Swedish Royal Palace spokeswoman Margareta Thorgren said this is “because of her pregnancy.”
Princess Madeline, 35, and her husband Christopher O’Neill, 43, have two children, a daughter, Princess Leonore, and a son, Prince Nicolas.
She is expecting her third child in March 2018.