According to the British Monarchy:
Remembering all those who fought and died at the Battle of the Somme, 1 July to 18 November 1916.
Her Majesty The Queen, accompanied by The Duke of Edinburgh, led the commemorations for the Centenary of the Battle of the Somme… The Queen placed a wreath at the Grave of the Unknown Warrior.
On Friday 1 July 2016, The Prince of Wales, The Duchess of Cornwall, The Duke and Duchess of Cambridge, Prince Harry and the Duke and Duchess of Gloucester attended a service of commemoration at the Thiepval Memorial in France.
The Princess Royal attended commemorative events in Canada.
To read the complete announcement by the British Monarchy, please click here.