British soldiers eating hot rations in the Ancre Valley during the Battle of the Somme, October 1916.
A line of British troops blinded by tear gas at an Advanced Dressing Station near Bethune, 10 April 1918.
Officers of 1/7th Battalion, King's Liverpool Regiment checking a map in trenches of the La Bassee Canal sector, 28 February 1918.
Two men of the 12th East Yorkshires wearing snow suits leaving their snow-covered trench on daylight patrol. Arleux Sector, 9 January 1918.
British troops of the 17th Battalion, London Regiment, 47th Division, crossing a muddy area in the Ancre Valley, Somme, October 1916.
Icicles hanging from the roof of a dug-out Bernafay Wood, Somme, November 1916.
Soldiers of the Lancashire Fusiliers cleaning a Lewis Gun. On the left can be seen the gas alarm horn and wind vane. January 1917 near Ploegsteert.
A sergeant of the Lancashire Fusiliers in a flooded dugout opposite Messines near Ploegsteert Wood, January 1917.
The Battle of Pilckem Ridge: Crossing the Yser Canal at Boesinghe, 31st July 1917.
Australian troops wait behind Quinn's Post, Gallipoli, after it was retaken on 29 May 1915.
Men of The Sherwood Foresters marching along the Amiens-St. QuentinRoad, near Brie, March 1917.
Australian troops walk along a duckboard track through the remains of Chateau Wood, Third Battle of Ypres (Passchendaele)
British troops advance to the attack through a cloud of poison gas as viewed from the trench which they have just left.
Battle of Albert. British troops asleep in a support trench previous to the attack on Beaumont Hamel, 7 a.m. July 1st 1916.
Troops of the 4th Battalion, Worcestershire Regiment (29th Division) marching to the trenches. Acheux-en-AmiÃÂ©nois, Somme, 27 June 1916.
A captured German pillbox nicknamed 'Gibraltar' in the ruins of Pozieres, Somme, 20th September.
A well concealed and revetted trench, between two-lines of trees. Gommecourt, given up by the Germans in March 1917.
A barbed wire gate in a trench system to form a block against raiders at Cambrin, 16 September 1917.
Officers of 12th Royal Irish Rifles wading through mud in a trench, Essigny, 7 February 1918.