In July 1916, an artillery observation-post was established at the “Cavalier”. The camouflage section came and erected there a strong steel cabin, loopholed towards the enemy side, and also provided with a periscope. A telephone wire was connecting that post to the Divisional Artillery Commander. But the month of may with its hard and bloody days the men had to contend with, were not to be forgotten, and a keen wish for vengeance was nursed by every one. Was the No “One” enemy trench not presenting itself to us in a similar way as our “Death Trench” to him? In fact, we were on the bridge-head on the right bank. The attack and destruction of that line was decided. On July 18^{th} 1916, after that several reconnaissances had made during the preceding nights, and thorough destruction fire switched on to the trench, a detachment of n^o 4 company of the IV^{th} Bat. of the 2^{nd} line Regiment, under the command of Lieutenants Loyse and Desenfans stormed it. The object of the raid was not to remain there, but the duty of the raiding-party was to “clean the place up” and keep it free of Germans a sufficient length of time to blow all the concrete shelters up, to render them unhabitable. The “cleaning up” was thoroughly done, but unfortunately Lieutenant Loyse having been dangerously wounded, could not give the signal which was to start the blowing of the charges, that sapper sergeant Billiet had placed, after having himself taken an ample share in the first part of the show. This raid is recorded as an example of the kind. All the dead and wounded of the party were brought back to our lines. The enthusiasm was at its highest, the confidence kindled, the regiment avenged. The sector was calm for a good while. The 17^{th} of October 1916, the German, roused once again, opened on our line, at kilometer 16, the most powerful bombardment, foreboding a new attack. But our gunners were on the watch, they directed at once a counter-bombardment so violently efficient that it must have taken out from the enemy’s mind the slightest wish to jump out of his haunts. Ten days later, the 2^d line regiment decided to do away with the “One” enemy trench, for good and all. From up the 27^{th} on to the 31^{st} of October detachment raided by night the accursed trench, they undertook the destruction of the shelters, turning the whole of No “One” line into real havoc. In the course of the years 1917 and 1918, the life at the kilometer 16 quietened down, the intervals between the bombardments and mortar duals lengthened, and were replaced by intermittant artillery and hand grenades fights. The “Cavalier and Death Trench” received then their final improvements. The first observation cabin having been demolished by gun fire, on April the 4^{th} 1917, a new one in concrete took its place, the upper trench became a platform, the liaison and signal post provided with ground telegraphy. The automatic rifles and bomb throwers multiplied.