German General Falkenhayn therefore chose Verdun for its vulnerability and also because he would not have to move many troops. Counting on the German superiority in heavy artillery, he will use the "Trommelfeuer" method:a "drum roll" artillery preparation which should make it possible to level the ground to be conquered.
The Germans amassed some 1,225 artillery pieces of all calibers in front of Verdun, including 542 heavy howitzers. On average, one can count a fast mortar of 210mm every 150m. They deploy 13 Krupp 420mm howitzers, 17 Skoda 305mm howitzers (Skoda later became Czechoslovakian), 2 380mm naval guns and ammunition accordingly, approximately 2,500,000 shells.
They massed 72 infantry battalions in buried shelters (stollen). Of the 20 divisions assigned to the operation, 10 are planned for the actual battle, the other 10 being reserved for a possible decisive battle on another sector stripped accordingly.
All these preparations cannot escape the attention of the defenders of Verdun who do not fail to report the information to the highest military authorities.
Thus Lieutenant-Colonel Driant, commander of the 56th and 59th Chasseur Battalions, took advantage of his position as a parliamentarian and member of the National Defense Commission to draw the command's attention to the sector.
Joffre sends a detachment of engineers, but it is very late. General Herr, head of the fortified region of Verdun, said himself “every time I ask for artillery reinforcements, GHQ responds by withdrawing two batteries from me! »
Since mid-January, the German preparations have been confirmed by the French intelligence services (2nd office), by aerial reconnaissance which takes disturbing photographs and by deserters from Alsace and Lorraine. Joffre remains deaf to this information.