King Harald V of Norway marked the 33rd year of his reign on Wednesday 17 January, with the anniversary coming just days after he sent a congratulatory message to the new King Frederik and Queen Mary of Denmark.
Harald became King following his father King Olav's death in 1991 and in 2016 he celebrated his Silver Jubilee.
While Queen Margrethe of Denmark's recent abdication has raised questions over whether Harald will do the same, in favour of his 50-year-old son Crown Prince Haakon, he declared in 2017 that he has no plans to abdicate.
Born on 21 February 1937 to Olav V of Norway and Princess Martha of Sweden, Harald became Crown Prince at the age of 20, upon his grandfather Haakon VII's death in 1957.
Harald shares a close bond with many of the European monarchs, including the late Queen Elizabeth II. Elizabeth was a second cousin to Harald and the pair shared the same great-grandparents, King Edward VII and Queen Alexandra, who were the father and mother of Norway's own Queen Maud.
He represented Norway in sailing at three consecutive Olympic Games from 1964 and took a stand over objections to his romance with commoner Sonja Haraldsen.
The couple went on to marry in 1968 and welcomed their first child, Princess Martha Louise, in 1971, and then son, Crown Prince Haakon, two years later.
Take a look at some of the best photos from Harald V's reign and life as he marks another year on Norway's throne.
Silver Jubilee, 2016
This official portrait of King Harald and Queen Sonja was released in 2016 to mark the King's Silver Jubilee.
The Norwegian royals celebrated Harald's 25th year of his reign with a series of events, including a lavish banquet with many of the European royal families in attendance.
Wedding day, 1968
The then Prince Harald with wife Sonja on their wedding day in 1968.
Sonja wore a silk wedding gown by Norwegian department store, Molstad and sported flowers in her hair instead of a tiara to secure her veil.
The couple had dated for nine years but there was controversy over their romance, as Sonja was a commoner.
Harald told his father Olav that if he was not allowed to marry Sonja he would not marry at all. This would have been a disaster as it would have ended the reign of his family and the Norwegian monarchy, as Harald was the sole heir to the throne.
First child, 1971
Harald and Sonja welcomed their first child, Princess Martha Louise, on 22 September 1971.
Although Martha Louise is two years older than her brother, Crown Prince Haakon, she did not feature in the order of succession at the time of her birth, because constitutional law at the time dictated that only males could inherit the Norwegian throne.
The law changed in 1990 but only applied to those born that year or later.
Females born between 1971 and 1990 were given succession rights but their brothers would still be before them in the line of succession.
Princess Martha Louise shares three daughters with her late husband, Ari Behn, (who died by suicide in 2019) – Maud, Leah and Emma.
Family of four, 1977
The King and Queen pictured with their young child, Martha Louise and Haakon, at their home in Oslo in 1977.
A kiss for Queen Elizabeth, 2015
King Harald and Queen Elizabeth II shared a close friendship, given their family ties.
When she became monarch in 1952, Norway was the first country outside the Commonwealth where Elizabeth paid a state visit.
William and Kate's royal tour, 2018
King Harald escorted the then Duchess of Cambridge to a banquet during Prince William and Kate's royal tour of Sweden and Norway in 2018.
Kate was pregnant with her third child, Prince Louis, at the time.
Royal wedding, 2001
King Harald and Queen Sonja celebrated Crown Prince Haakon's marriage to Mette-Marit Tjessem Høiby, on 25 August 2001 at Oslo Cathedral.
Mette-Marit was already a mother to Marius Borg Høiby, her son from a previous relationship.
She and Haakon later welcomed their children, Princess Ingrid Alexandra and Prince Sverre Magnus, in 2004 and 2005 respectively.
Family Silver Jubilee celebrations, 2016
King Harald and Queen Sonja were surrounded by their children and grandchildren at their Silver Jubilee celebrations in 2016.
The King and his heirs, 2016
The palace also released a portrait of the King with his two heirs, Crown Prince Haakon and Princess Ingrid Alexandra, to mark his Silver Jubilee in 2016.
Princess Ingrid Alexandra is second in line to Norway's throne after her father, Haakon, and is expected to become the country's second female monarch, after the 15th-century Queen Margaret.
Devoted grandfather, 2022
The King delivered a speech at a glittering gala dinner in honour of his granddaughter Princess Ingrid Alexandra's 18th birthday in 2022.
It marked Princess Ingrid Alexandra's first tiara moment, where she wore the Boucheron Pearl Circle Tiara.
Close cousins, 2017
King Harald was seated alongside Queen Elizabeth II at the 70th anniversary of the D-Day landings, where the pair enjoyed a chat and a giggle.
Reunited for the last time, 2018
King Harald and Queen Elizabeth II's last public engagement together was at a Anglo-Norse Society centenary reception in 2018.
The Norwegian king was among the European royals to pay his respects to the late Queen at her state funeral in London in September 2022.
Milestone birthday, 2017
The King and Queen both celebrated their 80th birthdays in 2017, with a big gala dinner held at the palace to mark the occasion.
