William and Kate to mark 100 years since Battle of Passchendaele

Last updated at 10:18
Poppies with messages written on them on display next to the Tyne Cot Commonwealth War Graves Cemetery, near to Ypres in BelgiumPA
Poppies with messages to the soldiers who died are displayed next to the Tyne Cot Commonwealth War Graves Cemetery in Belgium

The Duke and Duchess of Cambridge will join Prime Minister Theresa May in Belgium later to mark 100 years since the Battle of Passchendaele during World War One.

Half a million Allied and German soldiers were killed, wounded or went missing in three months of fighting.

Many drowned in the thick mud, caused by weeks of rain.

A service will be held in Ypres, where the King of Belgium and Prince William will lay wreaths at the Menin Gate.

What happened at the Battle of Passchendaele?
People look at the names of some of fallen soldiers on the Menin Gate in YpresPA
The names of 55,000 soldiers, who were never found, are listed on the Menin Gate in Ypres, Belgium

Officially known as the Third Battle of Ypres, Passchendaele was fought between 31 July and 6 November 1917 in northern Belgium.

About 275,000 Allied troops and 220,000 Germans died.

British troops hoped to push back the Germans from a ridge, near the Belgian town of Ypres during the three-and-a half month campaign.

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Watch Ricky's report about making World War One battlefields safe again

Thick mud clogged up rifles and stopped tanks, and ultimately, the fighting is believed to have won the allied forces only a small amount of ground.

On Monday, the anniversary of the start of the battle, events will continue with a special service held at Tyne Cot cemetery, where thousands are buried and commemorated.