Photos 1 and 2, Dammstrasse 28 O 3. Trenches could survive tremendous bombardment. The German trenches are relatively intact in the "after" photo, but the number of Germans in those trenches that survived to fight—and were willing to fight—was significantly reduced.

From "The infantry cannot do with a gun less": the place of the artillery in the British Expeditionary Force, 1914-1918 by Sanders Marble