World War One Centenary: Britain Remembers

Commemorations are taking place across Europe to mark the centenary of the day Britain entered the First World War.

An estimated 37 million people were killed or injured in the conflict which lasted from 1914 until 1918.

The Duke and Duchess of Cambridge attended a service in Liege to mark 100 years since the German invasion of Belgium at the start of World War One.

The Royals were received at L'Abbaye Saint-Laurent by King Philippe of Belgium, from where they walked to the Cointe Inter-allied Memorial for a service, during which Prince William gave a speech and spoke of the importance of reconciliation across Europe.

"We were enemies more than once in the last century, and today we are friends and allies," he said.

"We salute those who gave us our freedom. We will remember them."

Among the more than 50 heads of state joining them were French President Francois Hollande and German President Joachim Gauck.

William and Kate will attend a special ceremony at Belgium's St Symphorien Cemetery this evening, outside the town of Mons, where the solemn tributes to the fallen will continue.

It is one of a series of events marking Britain's entry into the Great War .

Across the Channel, the Prince of Wales, dressed in the uniform of a British admiral of the fleet, attended a Service of Remembrance at Glasgow Cathedral where the 1,400 invited guests included representatives of Commonwealth countries, senior military figures and charities.

He was joined by Prime Minister David Cameron, Deputy Prime Minister Nick Clegg, Labour leader Ed Miliband and Scotland's First Minister Alex Salmond, who all laid wreaths at the Cenotaph in George Square.

Speaking outside Glasgow Cathedral, Mr Cameron said the war "profoundly changed our world".

"It is right to commemorate this because this event had a massive impact on every community, every family in our country," he said.

"It is also right to remember the outbreak of the war because so many young British people thought they were rallying to a cause of defending the right of a small country, Belgium, to exist, and the prevention of the domination of Europe by one power.

"There are principles and thoughts that were in play at that time and are worth remembering today as well," he added.

In Folkestone, Prince Harry inspected a parade of troops - marking the route taken by millions of young men who marched through the Kent harbour town on their way to northern France and Belgium. For some, it was their last glimpse of British soil.

The Prince also officially opened a Memorial Arch in dedication to the veterans of the Great War .

On the other side of the globe, Australia and New Zealand marked the outbreak of the Great War with Prime Ministers Tony Abbott and John Key describing it as a conflict that shaped their nations too.

People are being urged to turn off their lights for an hour at 10pm to mark the moment Britain entered the war.