Looking across the valley from Soissons, we see the hills rising up from the river like a wall. They vary in height, from 200 feet in the west near Compiègne to 450 feet in the east near Craonne.[122] A nearer view of these hills shows us many spurs dipping down sharply into the vale, and between them steep-sided ravines and deep, narrow water-courses carved out by the short and rapid brooks. All the way from Compiègne to Craonne the wall of heights continues, with sometimes a bolder spur and sometimes a deeper ravine. In many of the valleys there are quarries which have been worked for centuries. The hollows from which the stone has been taken, the underground passages, and the heaps of refuse afford abundance of ready-made cover. The top of the plateau cannot be seen from the valley, nor from the high ground on the southern bank of the river, owing to the woods, which dip over the edges of the slopes and descend towards the stream. The lower slopes are, for the most part, steep and grassy, with enclosed coppices here and there. As you know, the plateau stretches northwards to La Fère and Laon, where it drops steeply to the plains of north-eastern France. The villages on the plateau are strongly built of stone. On the high ground, at an average distance of two miles from the stream, the Germans had dug their trenches. The position was perfect. It could not be seen from the high ground on the south side of the river, and it commanded the bridges crossing the stream and most of the roads leading to them. Along the crest runs a good highway, known as the "Route des Dames"--that is, the Ladies' Road; by means of this road the Germans were able to supply their line readily with food and ammunition. At the eastern end of the heights the ground falls away behind the road, and forms a deep hollow running parallel with it, thus providing excellent cover for the supports of the troops holding the crest. Von Kluck occupied the western section of the position, from the forest of Compiègne to the large village of Craonne. Beyond that place, at the old ferry of Berry-au-Bac, the German line crossed the river and continued along a flat ridge parallel with the right bank of the Suippe,[123] a tributary of the Aisne. This ridge, which was held by von Buelow's command, curves to the south-east, and runs about fifteen miles east of the city of Rheims. No better position for artillery could be desired than the crest of the ridge, for the slope in front of it is quite open and bare, and it can be swept by the guns in all its breadth. In some respects this position was stronger than the line of heights, for there was little or no cover for troops advancing upon it. Still farther to the east the German line rested on the Argonne, where the army of the Crown Prince was operating. Along this front, which was more than a hundred miles in length, two million men were now to engage.