Silent crowds who gathered outside Buckingham Palace yesterday broke into a tearful rendition of God Save The King following the news of the Queen's death.
A video clip posted to social media captures the moment mourners sang through their tears after learning she had died.
People had began to gather at the Palace gates during the afternoon while members of the Royal Family flocked to Balmoral to be with the monarch in her final moments.
The flag was lowered to half-mast as the news was officially announced at 6.30pm.
As the rainy weather reflected the sombre mood, a hopeful rainbow appeared in the sky at Windsor Castle, the Queen's favourite home.
Footage of the brief moment that crowds welcomed in the reign of King Charles by singing God Save The King was soon shared on social media.
One man can be seen visibly upset while other photos of the scene showed a tearful woman with her head in her hand.
By nightfall the crowd of people had grown from hundreds to thousands, braving the downpours to pay their respects.
John Loughrey, 67, wept as he said he "can't believe" the news and paid tribute to the "inspirational" Queen whose "duty always came first".
"I met the Queen twice. I gave flowers to her. I can't believe it," he told The Sun.
"She was inspirational. She served her duty - her duty always came first, her family next.
"She went downhill after the Duke of Edinburgh died. God save the Queen."
Mr Loughrey said he would be camping near the palace for 10 days as a mark of respect for the Queen before lighting a candle for her at Westminster Abbey.
Spontaneous chants of long live the King could be heard into the night as the new monarch was ushered in.
When the lights from the front facade of Buckingham Palace came on, the crowds cheered.
A line of London cabbies, parked their iconic black vehicles on The Mall as many 'made a beeline' to the Palace after hearing the news.
Michael Ackerman, a cab driver for 26 years, and friend Robert Caulder, who has driven a cab for 10 years were among them.
Mr Ackerman said that cab drivers had come to the Palace to "show our respect" for the monarch.
"We now know the Queen's passed, the only woman we've ever known, our constant in both our lives and we're showing our respect," he said.
Mr Caulder said he was one of the first cab drivers to arrive at The Mall after hearing the news on the radio as he drove along Tottenham Court Road.
Others gathered described the Queen as a 'wonderful' and 'a rock' as they proclaimed they were deeply affected by her passing.
Michael Hammond learned of the news when he saw the Union Flag being lowered to half mast.
"I'm absolutely gutted. I thought she embodied the British spirit," said the 23-year-old from Southampton.
The Queen's body will now be moved from Balmoral to the Palace of Westminster and is expected to arrive in London by royal train.
Royal fans and mourners will be able to visit and pay their respects at the Palace of Westminster with her for three days.
Plans for her funeral and national remembrance day are expected to be announced in the coming days.
Charles, who will now be known as King Charles III, gave a sombre statement as he led the nation in mourning yesterday.
“The death of my beloved mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family," he said.
