World War I was unlike any that had preceded it. At the war's outbreak, Europeans had expected the conflict to be short. However, combat soon bogged down into a stalemate. On the western front, both sides dug complex trench networks that stretched for hundreds of miles across Belgian Flanders and northern France. Industry mass-produced artillery, machine guns, and ammunition at extraordinary rates while railroads carried a continuous flow of munitions and soldiers to the front. At the same time, the combatants pursued technological means to break the stalemate. The results—tanks, poison gas, and the military use of airplanes—were too new to have dramatic effects on the outcome of the Great War, but they would transform future warfare.