The success was so complete and crushing that for a short time there was a gap in the German front line. Scattered units hastily got together were thrown into the breach where, crouching in the shell-holes, they resisted desperately with rifle and machine-gun, and held their ground for a whole day, without any reserve support. On March 24, 1918, the German columns forced the line of the Tortille stream and entered Bouchavesnes, thereby bringing about the fall of Péronne--outflanked from the north--and the retreat of the British towards the Ancre. The village was reconquered on September 1 following, after sharp fighting. [Illustration: BOUCHAVESNES.] _After passing by Bouchavesnes, N. 37 ascends another crest_ (see fortified quarry on the left), from the top of which there is a magnificent panorama: _on the left_, the Valley of the Tortille (a small tributary of the Somme); _in the valley_, the Northern Canal and Village of Allaines; _opposite_, the Mont-St.-Quentin; _on the right_, the Valley of the Somme. The portion of the National road which is now followed was the scene of furious, bloody fighting in 1916. In their attempt to outflank Péronne, the French encountered strong German forces which stubbornly held their ground. Traces of the desperate fighting are seen all along the way: stumps of shattered trees, mine-craters and shell-holes in the fields, soldiers' graves, etc. [Illustration: NEAR PÉRONNE. RUINS OF BRIDGE OVER THE CANAL DU NORD, ON THE N. 37.] _Cross the Northern Canal by temporary bridge._ [Illustration: THE CANAL DU NORD FORMED A BITTERLY DISPUTED LINE OF RESISTANCE.] This canal, which connects the Somme with the rivers of northern France, was not quite finished when the war broke out. Its bed was excavated, but not yet filled with water, so that it formed a ready-made line of resistance. The Germans were unable to hold it in 1916, and the British were likewise driven from it by the German thrust in 1918. [Illustration: WHAT THE GERMANS SAW FROM THEIR OBSERVATION-POST ON THE MONT-ST.-QUENTIN.] _Immediately beyond the canal, the small, ruined village of =Feuillancourt= is crossed_. On September 12, 1916, the French gained a footing on Hill 76, west of the village. This was the nearest position to Péronne reached in 1916, to the north of the town. _Follow N. 37 to =Mont-St.-Quentin=._ Mont-Saint-Quentin Built along the National road, 2 km. north of Péronne, on a hill having an altitude of 325-390 ft., the village of Mont-St.-Quentin possessed, until the Revolution, an important abbey, which was founded in the early Middle Ages. The hill, now famous, rises in front of Péronne, and forms the immediate defence of the town. The Germans had, prior to the Franco-British offensive of 1916, posted their heavy artillery there and built powerful entrenchments.