Most of the land on the Western Front was only a couple of feet above sea level. As soon as soldiers began to dig trenches they would invariably find water just below the surface. Constantly standing in water caused trench foot and other ailments. In an attempt to alleviate the problem, wooden planking, known as duckboards, were placed at the bottom of trenches and across other areas of muddy or waterlogged ground.
Australian soldiers walking on duck-boards at Passchendaele
