Cardiff, UK - Thousands of people gathered at Cardiff Castle to hear Charles proclaimed King in Wales.

More than 2,000 people were allowed inside the grounds after the gates opened at 10:00 AM.

Hundreds more lined the streets outside the castle walls, including two protesters holding signs reading: "Not our king!"

The former Prince of Wales ascended to the throne following the death of his mother, Queen Elizabeth II, on Thursday. He was then formally proclaimed King at a historic ceremony in St James's Palace in London following a meeting of the Accession Council during which he swore an oath to privy counsellors.

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Proclamations will take place across the UK on Sunday, including Wales, at about midday. Prior to the Proclamation, 26 men of the 3rd Battalion the Royal Welsh – supported by the Band of the Royal Welsh – were marching from City Hall at 11:25 AM along the Boulevard de Nantes, North Road, and Duke Street to the castle.

They were accompanied by the regimental mascot, a Welsh billy goat called Lance Corporal Shenkin IV, and Goat Major Sergeant Mark Jackson.

Inside the castle, the Wales Herald of Arms Extraordinary, Tom Lloyd, made the Proclamation in English, and the Lord-Lieutenant of South Glamorgan, Morfudd Meredith, proclaimed King Charles in Welsh.

After the readings, members of 104th Regiment of the Royal Artillery fired a 21-gun salute before the singing of God Save The King and Hen Wlad Fy Nhadau, Wales' national anthem. It was the third time in three days that artillery fire has resounded across the Welsh capital to mark both the queen's death and the accession of her son to the throne.

Flags on the castle and council buildings, which had been flying at half-mast, were returned to full-mast on Saturday, to coincide with the Reading of the Principal Proclamation of the new monarch in London. Flags returned to half-mast at 1:00 PM on Sunday after the Proclamation is read in Cardiff.

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The Senedd has been recalled at 3:00 PM to allow members to pay tribute to the queen. All other business has been suspended until after the state funeral on Monday, September 19.

Welsh Secretary Robert Buckland attended the Proclamation ceremony, along with Wales First Minister Mark Drakeford and opposition leaders.