King Charles III was joined by other senior royals on foot, as they followed the hearse carrying his mother's coffin in Scotland's capital.
He was joined by Prince Andrew, Princess Anne and Prince Edward as their mother's coffin was taken through the streets and then carried into St Giles'.
A wreath on her coffin consists of nine different flowers, including white spray roses, white freesias, white button chrysanthemums and dried white heather.
Her coffin was carried in to the cathedral, where it is due to rest for 24 hours.
King Charles III inspects the Guard of Honour as he arrives for the Ceremony of the Keys at the Palace of Holyroodhouse, Edinburgh
Phil Noble
Queen Elizabeth II's coffin in Edinburgh
POOL
As the coffin made its way through the cathedral, the choir sang Thou Wilt Keep Him In Perfect Peace, Whose Mind Is Stayed On Thee.
During the service, First Minister Nicola Sturgeon, dressed in an all black outfit and black hat, read the first lesson Ecclesiastes 3: 1–15.
At the end of the service, the King and Queen Consort, followed by members of the Royal Family, made their way out of the place of worship.
Members of the congregation bowed and curtseyed as they walked past.
Applause could be heard when the Royal Family stepped out into the Edinburgh sunshine.
King Charles III in Edinburgh
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The King will later attend the Scottish Parliament to receive a motion of condolence, while Queen Elizabeth II's coffin will rest a St Giles' for 24 hours.
Later on Monday evening, the King will hold a vigil at the cathedral alongside other Royal Family members.
Earlier in the day, he addressed peers and MPs in Westminster Hall.
The new monarch accepted addresses of condolence from the House of Lords and the House of Commons at the ancient venue.
He said: “As Shakespeare said of the earlier Queen Elizabeth, she was a pattern to all princes living.”
In reply to addresses from both Houses of Parliament, Charles said: “Parliament is the living and breathing instrument of our democracy.
“That your traditions are ancient we see in the construction of this great hall and the reminders of mediaeval predecessors of the office to which I have been called and the tangible connections to my darling late mother we see all around us”.
He concluded his first formal address to Parliament as King by saying: “We gather today in remembrance of the remarkable span of the Queen’s dedicated service to her nations and peoples.
“While very young, Her late Majesty pledged herself to serve her country and her people and to maintain the precious principles of constitutional government which lie at the heart of our nation.
“This vow she kept with unsurpassed devotion. She set an example of selfless duty which, with God’s help and your counsels, I am resolved faithfully to follow.”
Following the King’s address, the audience stood and the national anthem was sung in Westminster Hall.
The King and Queen Consort then departed, followed by the Lords and Commons Speakers.
First Minister Nicola Sturgeon
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