By Ruth Comerford, BBC News
Tens of thousands of people turned out to watch King Frederik X succeed his mother as the monarch of Denmark, in a historic moment for the nation.
Blinking back tears, King Frederik told a cheering crowd outside Christiansborg Castle that he hoped to become "a unifying king" for the future.
He also praised his mother, who formally abdicated an hour earlier, ending exactly 52 years on the throne.
She is the first Danish monarch to voluntarily abdicate in over 800 years.
Despite being billed as a low-key affair, a sea of people gathered outside Christiansborg Castle to witness the succession on Sunday.
Speaking the words, "Long live king Frederik the tenth" three times in a ceremony on the balcony of the palace, Prime Minister Mette Frederiksen proclaimed Frederik as the King of Denmark, Greenland and the Faroe Islands.
In his first speech to the people, King Frederik said his task of becoming "a unifying king of tomorrow" is something he has approached all of his life.
"It's a task I've taken on with pride, respect and joy."
He added that his mother would always be remembered as an "extraordinary" regent.
King Frederik appeared to grow emotional at the sight of the crowd, wiping away a tear as he took in the celebratory spectacle.
He was joined on the balcony by their four children, including 18 year-old Crown Prince Christian, the new heir to the throne.
And a kiss between King Frederik and his wife, the Australian-born Queen Consort Mary, was met with whoops and cheers by the crowd.
Crowds lined the streets across the city to bid farewell to Queen Margarethe - who was the world's only remaining female sovereign.
The 83-year-old revealed her unprecedented decision to step down during a live televised address on New Year's Eve.
In the broadcast, she revealed that the decision was made after a period of reflection following surgery on her back in early 2023.
"The surgery naturally gave rise to thinking about the future - whether the time had come to leave the responsibility to the next generation," she said, offering her thanks to the Danish public for their support over the years.
She will keep her title as Queen, while the King's wife retains the title of Queen Consort.
King Frederik, 55, now helms Europe's oldest monarchy.
The British monarch King Charles and Queen Consort Camilla sent their best wishes to new monarch, paying tribute to the "many years of service" Queen Margarethe had given to Denmark.
This story was originally published by the BBC.