Diaries from British soldiers describing life on the frontline during World War One are being published online by the National Archives.

Events from the outbreak of war in 1914 to the departure of troops from Flanders and France were recorded in official diaries of each military unit.

About 1.5 million diary pages are held by the National Archives and a fifth have been digitised so far.

The project is part of the government's World War One centenary programme.

Each unit in World War One was required to keep a diary of its day-to-day activities....