What was the Christmas Truce?
18 December 2013 Last updated at 06:22 GMT
World War I affected nearly everyone in Britain as men and boys were sent to fight in some of the toughest conditions.
One of the most interesting stories to come out of the conflict was the Christmas Truce, when German and British soldiers went into no mans land to shake hands, sing carols and play a football game.
Now children from the UK have travelled to Ypres to take part in a football game and find out what life was really like for the soldiers.
Martin went along with them.