Behind thick belts of sandbags, barbed wire, and metal sheets, soldiers watched each other across no man's land with careful eyes. In quiet times, trench warfare was a war of attrition and harassment. Snipers and camouflaged marksmen were in constant search of negligent soldiers who held their heads too long above the parapets. Some forward trenches were only a short distance away from each other, and soldiers bombarded each other with explosives thrown by small catapults or fired by trench mortars and mine-throwers. The German trenches were particularly sophisticated. Reinforced with deep dugouts and cement bunkers, they were secure shelters for their infantry against the heavy shelling of their enemies. Built in narrow zigzag formations to protect against shrapnel and incoming grenades, reserve and communication trenches connected machine gun emplacements and grenade pillboxes with each other.
When the front became active, so too did life in the trenches. Sudden artillery barrages usually meant a coming attack, and the defenders would hurry out of the dugouts and bunkers as soon as the shelling stopped and bring up machine guns and rifles. Brutal close combat followed if the attacker manages to break into the lines. Without room to maneuver, soldiers had to step over the mutilated corpses of the dead and wounded. The zigzag lines now provided enough cover for close quarters rifle fire and grenades, and whole squads were killed in moments by storms of steel that raged in the narrow earthworks.