The Danish royals shared their meeting on Instagram to warmly welcome the Duchess during a reception at Amalienborg.
They revealed that the opulent building they met in also shared a connection to the British family because it's named after the Danish Queen and Queen Elizabeth's great-great-grandfather.
"The familial bond between the two royal families thus goes back many years," read the post's caption.
In a statement released by Kensington Palace, they echoed a similar sentiment as they honoured Queen Margrethe, who is celebrating 50 years on the throne and Queen Elizabeth, who is marking 70 years.
"A timely reminder of the longstanding relationship between the two Royal Families and will coincide with The Platinum and Golden Jubilees being enjoyed this year," read the statement.
Another Instagram post from the royal account features Mary and Kate, 40, walking across the palace grounds to have a private lunch at Frederick VIII's Palace.
After sharing their meal, the royals visited the Danner Crisis Centre, which helps support women and children exposed to domestic violence, which is supported by The Mary Foundation, which Mary founded in 2007.
The last time the Duchess and Princess met in Copenhagen was in 2011 when she visited with her husband Prince William after they got married, making the 11 year reunion even more special.
This story originally appeared on our sister site, Now To Love.