Amiens cathedral (begun 1220 AD)
Amiens is not far from Reims, in northern France, and when the bishop of Reims began building a big new cathedral in 1211 AD, naturally the bishop of Amiens wanted one too. In fact, Bishop Evrard of Amiens was determined to have the biggest cathedral in France, so he built his nave 138 feet high - 13 feet higher than Reims, and almost as high as the dome of the Pantheon in Rome.
The builders began with the front, or facade, of the cathedral. Like Notre Dame of Paris a generation earlier, the facade of Amiens has three big doors on the bottom level, a gallery and a row of statues across the middle, and a huge rose window (43 feet in diameter). But the facade of Amiens cathedral emphasizes vertical lines more than the earlier Notre-Dame of Paris, which has stronger horizontal lines. Amiens' facade is also deeper, so there are more contrasts between light and shadow.
Inside the cathedral, there's the same four-part groin vaulted roof as at Chartres, Rouen, and Reims, supported by the same kind of flying buttresses on the outside. At the crossing, though, you can see a more complicated pattern of ribs - the first example of this more complicated vaulting in France.
Because the nave at Amiens is very narrow, it seems even higher than it really is. The side aisles are also very high, which adds to the effect.
Cathedral: The Story of Its Construction, by David Macaulay (1981). Beautiful drawings and clear text explain exactly how medieval craftsmen built a cathedral, from foundation to the stained glass windows. Easy reading.