Trench warfare was a valuable method for reinforcing natural boundaries and creating a line of defence. For example, at the Battle of Stalingrad, soldiers on both sides dug trenches within the ruins. In addition, before the start of the Battle of Kursk, the Soviets constructed a system of defence more elaborate than any other they built during World War I. These defences succeeded in stopping the German armoured pincers from meeting and enveloping the salient.
(Photo source - Sergei Loskutov / News in pictures TASS)