This route leads from Cherbourg to Avranches.
The American allies did not come farther in Normandy because of the Normandy landscape. The Normandy landscape consists of walls and bushes and the modern weapons could not handle this. If a tank drove through a wall he becomes a beautiful target for the Germans. Throwing shells in the bushes did give any results either. The Germans did use the hedge rows very well for hiding there weapons, mortars and canons. The Americans were held back and suffered heavy losses. Then, an ingenius crewman made a cutting blade for the front of the tanks that allowed them to cut pathes through the hedge rows.
On July 25th, the allies started operation Cobra. This operation of general Bradley intended to advance southwards near the beaches to reach Avranches and liberate the next region, Bretagne. By this way, the allies went around the Germans in the south. At the same time, the Germans bombarded most of the villages on the route. So the villages were all mostly destroyed.
In Avranches are many roads crossing each other to Bretagne, Paris and Villedieu. The Germans did not defend this strategic point very well and Avranches was liberated almost without fighting.