Surrounded by a sea of red ceramic poppies in the former moat of the Tower of London, the Queen laid her own floral tribute to those who paid the ultimate sacrifice.
Blood Swept Lands and Seas of Red was created by ceramic artist Paul Cummins and by Armistice Day on November 11 there will be 888,246 ceramic poppies planted, one for each British and Colonial death during the conflict which began 100 years ago.
Mr Cummins, who met the Queen and the Duke of Edinburgh during their visit to the Tower said: “I was inspired to create this installation after reading a living will by an unknown soldier who we think may have been from Derby.
“I approached the Tower as the ideal setting as its strong military links seemed to resonate.
“The installation is transient, I found this poignant and reflective of human life, like those who lost their lives during the First World War. I wanted to find a fitting way to remember them.”
Stage designer Tom Piper helped Mr Cummins make his vision a reality along with a team of 8,000 volunteers who installed the flowers.
When the Queen and Duke first arrived at the imposing Tower of London they were met by its Constable, General the Lord Dannatt, the former head of the British Army, and Colonel Richard Harrold, Governor of the medieval fortress.
In an ancient ceremony they surrendered their ceremonial keys of office to the Queen and she symbolically touched the objects.
The Queen and Duke walked through a path in the poppies to a small mound where Yeoman Warder Jim Duncan was holding the royal wreath.
The Queen touched it and it was carefully placed on a small mound by the Yeoman Warder.
Hundreds of spectators lined the perimeter of the moat watching the solemn event and kept a respectful silence.