Well, perhaps it's time to go through (what I consider to be) the closest royal friendship of them all. - So, here's a summary of the special relationship between Queen Margrethe II and Queen Sonja:
Their conversations:
They became friends right after Sonja's wedding to Crown Prince Harald in 1968. - And both Queens have said in interviews with Norwegian media over the years that they can talk about everything.
Here is a quote from Queen Sonja's speech during the 80th Birthday gala dinner at the Royal Palace in Oslo last year:
Dear Queen Margrethe, you have been a vital support all since I became part of this family. In addition to being an invaluable adviser, you are a close friend with whom I share common interests like nature and the arts. Thank you so much for all our walks and talks, and for your ability to discover comic aspects on special occations!
Their skiing/trekking tours:
Well, there have been quite a few of them over the years - and here's a dramatic story from 1985:
Nettavisen article from 2005 - translated by me:
Dronninger i livsfare - Nettavisen
In a new book, Queen Margrethe talks about a dramatic ski trip together with Queen Sonja. The Danish Queen believes the trip could have cost them their lives.
Queen Margrethe released the book "Margrethe" on the occasion of her 65th birthday. Here she tells (among other things) about the ski trips with Queen Sonja.
One of the trips, 33 years ago, is a dramatic memory. Then the two Queens were on tour with the mountain hiker and war hero Claus Helberg. Along the way they were amazed by the weather-changes, and when they reached the cabin where they were to stay, they were completely worn out.
"In that case, under no circumstances could anyone come and save us. I was excellently aware that if someone had to give up, it could really be a matter of life and death,'' she says, according to Dagbladet.
According to Queen Margrethe, this event has led to her and Queen Sonja having a very special relationship.
''You get a very special relationship with people you've tested boundaries with. There is a special kind of glue in such a friendship.''
Yes, I know we are not allowed to translate entire articles, but this one was very short (and it's not a direct translation).
And yes, I tried to put up a google translation, but the result was pretty bad, so I dropped it.
--------------------
Claus Helberg (who was mentioned in the article) was with them on several trips, and when he turned 80 in 1999, both Queens were present in Oslo to celebrate him.
Read more about him here:
Claus Helberg - Wikipedia
Claus Helberg, 84, War Hero In the Norwegian Resistance - New York Times
Photos from his 80th birthday - with his two queenely friends:
https://scanpix.no/spWebApp/preview/editorial/sf0a0661
https://scanpix.no/spWebApp/preview/editorial/sf098f41
--------------------
But back to the two Queens and their friendship. - Here are some photos of their ski trips:
Winter holiday in Gausdal (Norway) with King Harald, Queen Sonja, QMII, Haakon, Märtha, Frederik and Joachim in 1979, but no pictures of Henrik:
Kronprinsfamilien i Gausdal, mars 1979 - NTB Scanpix gallery with 9 photos
Winter holiday in Alvdal (Norway) with QMII, Queen Sonja and Claus Helberg in 1990:
Dronning Sonja og Dronning Margrethe på Alvdal 1990 - NTB Scanpix gallery with 8 photos
Winter holiday in Northern Norway with QMII, Queen Sonja and Claus Helberg in 1993:
Dronning Sonja og Dronning Margrethe i Nord-Norge 1993 - NTB Scanpix gallery with 10 photos
QMII and Queen Sonja on a visit to Greenland in 1994. - Two photos:
https://scanpix.no/spWebApp/preview/editorial/sf0053ca
https://scanpix.no/spWebApp/preview/editorial/sf005413
What they do when they are together:
Well, QMII (in contrast to the 80-year-old Queen Sonja) is no longer able to go on skiing/trekking tours, but she still spends her winter holidays in Gausdal (Norway).
QMII's winter holiday 2017:
When the NRF arrived back in Norway from their winter holiday in South Africa (where they had celebrated the King's 80th birthday), QMII spent her last day in Norway, with Queen Sonja in Oslo.
They first visited the Munch Museum, followed by a trip to the National Opera and Ballet (where they looked at costumes and stuff).
How do I know this? Because Queen Sonja said it in a television interview with NRK (Norwegian Broadcasting Corporation) in July to celebrate her 80th Birthday.
Those who understand Scandinavian can watch Queen Sonja talk about it here - from 20:20 in this video:
Gåva frå Kongen - Dronning Sonja fyller 80 år - NRK1
QMII's winter holiday 2018:
King Harald (who is a bit frail now) and Queen Sonja were in Uruguay to rest and prepare for their state visit to Argentina. - So there was no meeting between the two Queens this year.
Royal Central article (from March) about it:
Queen Margrethe on holiday in Norway – Royal Central
Queen Sonja would definitely like to receive her good friend, Queen Margrethe, on her winter holiday in Norway, but Queen Sonja has travelled abroad on vacation herself. The Queen will, therefore, not this time meet any of her Norwegian colleagues and good friends before King Harald and Queen Sonja travel to Argentina on state visits.
“Unfortunately, Queen Sonja is unable to see her good friend Queen Margrethe, as Queen Sonja is currently on a long-planned private trip abroad. So she is not at all in Norway during Queen Margrethe’s visit,” said a statement from the Royal Court to the Danish magazine Billed Bladet.
Queen Margrethe and Queen Sonja have a close friendship. Every year they have gone skiing together, but in he recent years the Danish queen has not gone skiing anymore. Then the two friends have, therefore, been observed together at various museums in Oslo, Norway’s capital.