A number of my posts mention Butte Vauquois. It was a high hill in the Meuse-Argonne region. Before the war, the village of Vauquois was on top of the hill. But after the war started, the Germans invaded France, and half the hill was occupied by the German Army and half by the French. Villagers obviously evacuated, so that today, the village is at the bottom of the hill.
Each side tunneled into the hill to get under the other side's trenches, planting explosives to blow up the trenches and open a gap in the line. This deadly nonsense continued to the point where one side would listen for the other side's tunneling and then tunnel under the tunnels.
By the time my father's machine-gun crew began firing at the butte on September 26, 1918, the Germans had taken possession of the entire hill. The emplacements on the hill could hold a large German force, but the garrison was greatly reduced by the time of the attack. The defenders surrendered to the Americans rather quickly.
Among the things my father brought back and passed down to me is an aerial photograph of Butte Vauquois as it looked in 1918. I don't know how my father acquired this photograph. You can see the big craters left by tunneling explosions. Trenches are also visible to the left and right of the craters. I believe that this was taken from an airplane west of the hill, so east is at the top of the image.