Since Abbott Suger was also enlarging the church, the chapels merged to form what seems to be a second ambulatory. Ribbed groin vaults and pointed arches were in use throughout. The pointed arches, no matter the width of the base, could be stretched to any height, and became a fundamental element to the ribbed groin vault. .
The scholar H. W. Janson describes the Abbey of St. Denis this way, " the entire plan is held together by a new kind of geometric order: it consists of seven identical wedge-shaped units fanning out from the center of the apse. This double ambulatory is a continuous space, whose space is outlined by a network of slender arches, ribs, and columns that sustains the vaults."" .
With this now in place, the area is seemingly weightless and open compared to the solid rigidity of the Romanesque churches. This complex plan has given way to large stained glass windows that can now expose the inner chambers to a luminosity that was not available before these advances in architecture. Other scholars have gone so far as to say that the walls have become "translucent- due to the overall magnitude of the stained glass windows that are used. The burden of the vaults is transferred to the .
buttresses, which are placed at integral points against the cathedral's outer walls. .
"'Harmony' (that is, the perfect relationship among parts in terms of mathematical proportions or ratios) is the source of all beauty, since it exemplifies the laws according to which divine reason has constructed the universe,"" says Janson. This superlative structure shows the capacity of man through God.
As a friend of Abbot Suger, the Bishop of Chartres was told about the ideas Suger had concerning the architectural planning of St. Denis. The Bishop began rebuilding his cathedral in 1145 with these "new- concepts in mind. Some fifty years later, all but the west fazade had burned down. It was this second rebuilding that makes Chartres renowned.