It was on Sunday, the twentieth of December, that the Battle of the Dunes began and the flames of war burst out afresh. The dunes lay between the North Sea and the Yser River in West Flanders and consisted of a stretch of sandy hillocks reaching from Coxyde to Nieuport les Bains. The Belgians had entrenched these dunes in an elaborate and clever manner, shoveling the sand into a series of high lateral ridges, with alternate hollows, which reached for miles along the coast. The hollows were from six to eight feet deep, affording protection to the soldiers, who could nevertheless fire upon the enemy by creeping up the sloping embankments until their heads projected sufficiently to allow them to aim, when they could drop back to safety.