World War I: Germany and France

September 13, 1914: When the Germans turned to face the pursuing Allies on 13 September, they held one of the most formidable positions on the Western Front. Between Compiègne and Berry-au-Bac, the Aisne River winds westward and is about 100 feet (30 m) wide, ranging from 12–15 feet (3.7–4.6 m) deep. Low-lying ground extends one mile (1.6 km) on each side, rising abruptly to a line of steep cliffs 300–400 feet (91–122 m) high, then gently levelling to a plateau.

The Germans settled on the higher northern side 2 miles (3.2 km) beyond the crest, behind a dense thicket that covered the front and slope. Low crops in the unfenced countryside offered no natural concealment to the Allies. Deep, narrow paths cut into the escarpment at right angles, exposing any infiltrators to extreme hazard. The forces on the northern plateau commanded a wide field of fire.

In dense fog on the night of 13 September, most of the British Expeditionary Force (BEF) crossed the Aisne on pontoons or partially demolished bridges, landing at Bourg-et-Comin on the right and at Venizel on the left. At Chivres-Val east of Venizel, there was an escarpment the Germans had selected as their strongest position.