Prince William, Kate and Prince Harry mark the Somme 100 anniversary in France

Prince William, Kate and Prince Harry paid their respects at the Somme Centenary commemorations in France at a vigil on Thursday night (June 30). The trio will be joined by Prince Charles, the Duchess of Cornwall and the Duke and Duchess of Gloucester on Friday (July 1) for additional events.

The battle of Somme took place on 1 July 1916 and is known as the deadliest battle in British history, with around 20,000 dead. The royal family are attending events across the Commonwealth to mark the battle's 100th anniversary.

TAP TO VIEW GALLERYPrince William Kate and Prince Harry pay respect Prince William and Kate attended a vigil at the Thiepval Memorial

William, Kate and Harry showed their respects by attending a vigil at the Thiepval Memorial on Thursday evening. The memorial commemorates British soldiers who died without graves and was lit up for the first time ever in honour of the occasion.

They looked moved as they heard of the one million dead (481,842 British and 250,000 French) in the largest and bloodiest battle of the First World War. Historian Glyn Prysor welcomed the royals to the site and showed them around the 45m (150ft) high memorial.

Prince Harry, Duchess Kate and Prince William chatting with Historian Kate looked elegant in a black Missoni coat

While Prince William and Prince Harry looked smart and sombre dressed in blue suits, Kate looked demure in a $1,460 Missoni coat and black dress.

The Duke and Duchess of Cambridge, both 34, and Prince Harry, 31, are not the only royals to attend commemorative events.

The Queen and Prince Philip remained in the UK to attend an evening vigil at Westminster Abbey, while Prince Andrew is due to attend the National Commemorative Service in Manchester on Friday. Princess Anne has travelled to Newfoundland to commemorate soldiers who died in battle in Beaumont-Hamel.

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