Trench warfare
Trench warfare prevailed on the Western Front from late 1914 until the Germans launched their Spring Offensive on 21 March 1918. After the buildup of forces in 1915, the Western Front became a stalemated struggle between equals, to be decided by attrition. Frontal assaults, and their associated casualties, became inevitable because the continuous trench lines had no open flanks. Casualties of the defenders matched those of the attackers, as vast reserves were expended in costly counter-attacks or exposed to the attacker's massed artillery. There were periods in which rigid trench warfare broke down, such as during the Battle of the Somme, but the lines never moved very far. The war would be won by the side that was able to commit the last reserves to the Western Front.
Role of geography in World War I
Trench Warfare was common during WWI, although it was not exactly the healthiest or morale-boosting experience for soldiers living in the trenches. They were constantly wet and water would often build up to several inches. Urine, body odor, poison gas, bad food, rats, little clothing, and misery all defined the trench lifestyle. Diseases such as Trench Foot emerged and close quarters caused infection to be passed from one person to another and from rats and bugs to humans as well. Loud bombs could often cause deafness and long periods in the trench often led to mental illness as well.