William and Kate make surprise appearance at Gallipoli ceremony to join Queen

The Duke and Duchess of Cambridge have made a surprise appearance at a poignant ceremony honouring those who died in the Gallipoli campaign.

William and Kate joined the Queen and Duke of Edinburgh at a wreath laying service held at a war memorial on the monarch's Sandringham estate.

The Cambridges were not scheduled to attend the ceremony which marked the 100th anniversary of the end of the disastrous First World War campaign on the Gallipoli peninsula.

But after attending a traditional Sunday service at Sandringham's St Mary Magdalene Church with the Queen and Philip, they walked behind the monarch to the nearby war memorial cross.

The Duchess, who celebrated her 34th birthday yesterday, was joined at church by her parents Michael and Carole Middleton and siblings sister Pippa and brother James.

The Middletons are likely to have helped William in throwing a celebratory party for Kate at the Cambridges' Norfolk home of Anmer Hall.

The Queen and Duke of Edinburgh, who is patron of the Gallipoli Association, stood still as the Last Post was played by a bugler and a minute's silence was observed.

Then, with solemnity and quiet dignity, the Queen and Duke each placed a wreath at the war memorial dedicated to local men who fought in the Great War and paid the ultimate sacrifice.

The Gallipoli land campaign against Turkey was one of the major engagements of the First World War, involving more than 400,000 British and around 140,000 Commonwealth and Irish servicemen.

At dawn on April 25 1915, waves of Allied troops launched an amphibious attack on the strategically important peninsula, which was key to controlling the Dardanelles straits, the crucial route to the Black Sea and Russia.

But the plan backed by Winston Churchill, then First Lord of the Admiralty, was flawed and the campaign, which faced a heroic defence by the Turks, led to stalemate and withdrawal eight months later.

Around 58,000 Allied troops died, including 29,500 from Britain and Ireland, over 12,000 from France, 11,000 from Australia and New Zealand and 1,500 from India.

Conditions were hellish as more than half a million Allies faced heat, flies, dysentery and eventually, extreme cold. The Turks suffered 300,000 casualties, with an estimated 87,000 killed.

The last Allied troops were withdrawn on January 9 1916.

The war memorial was erected by the monarch's grandparents King George V and Queen Mary, and among the men from the 5th Battalion Norfolk regiment it honours are some who died in the Gallipoli campaign.