While these strongholds in Alsace-Lorraine were thus being reduced, Verdun still intercepted the line of railway which formed the shortest line of communication with Germany.
This place, too, was made quite storm-free by high walls and deep wet ditches; but, on the other hand, it was surrounded by a ring of heights whence it could be seen into, and at the foot of these heights villages and vineyards favoured an approach to within a short distance of the outworks.
The fortress was armed with 140 guns and abundantly victualled, and the garrison, which had been supplemented by escaped prisoners, was 6000 strong. A bombardment by field-artillery had already proved perfectly ineffectual. For a long time Verdun was only under observation, at first by cavalry, and afterwards by a small mixed force. At the end of September the 65th Regiment and twelve companies of Landwehr assembled under General von Gayl before the east face of the place. It was not till October 9th that two companies of fortress-artillery brought up some French heavy guns from Toul and Sedan. The infantry now advanced to within a few hundred paces of the west and north fronts and there established itself. Under this cover the construction of the batteries was begun on the evening of October 12th.
The heavy ground after the rain, and the rocky subsoil very thinly covered, made the work uncommonly difficult, yet by next morning fifty-two guns were able to open fire. But the fortress replied with such effect that before noon two batteries on the Côte de Hayvaux on the westward were reduced to inaction.
In the course of this three days' artillery engagement, 15 German guns were placed out of action, the artillery lost 60 men and the infantry 40. The disabled guns on the walls of the enemy were constantly replaced by fresh ones.
The garrison, which was far stronger than the besiegers, now assumed the offensive. During the stormy night of the 19th--20th, the picquets on the Hayvaux were overpowered, and the guns in the battery there were spiked. On the 28th a sortie in greater force was made. The French climbed up Mont St. Michel, lying northward of Verdun, and destroyed the breast-works and bomb-proofs of the batteries, from which, however, the guns had been withdrawn. Another body pushed up the Hayvaux, and as the soaked state of the ground prevented the guns from being withdrawn, they were totally disabled. The villages in the neighbourhood were also occupied by the French.