
Elevation of Amiens cathedral (begun 1220 AD)
Where Chartres cathedral had a full gallery above the side aisles, Amiens has only a thin false gallery like Reims, with windows behind it that let in more light.

Amiens transept
In each arm of the transept, there is a huge rose window, with more windows beneath it. At Chartres the stone ribs of these windows made a fairly simple flower shape, but here at Amiens the stone ribs have gotten all twisted, so that they look like flames. Art historians call this “Flamboyant” Gothic, after the French word for flames, “flambes”. Today “flamboyant” means showoff-y, and that’s what these windows kind of are.
Just like at Notre Dame of Paris, the chapels in the side aisles were added later, so that the priests could each celebrate Mass every day.

Amiens labyrinth
Like Chartres, Amiens also has patterns of black and white marble on the floor. One part of the design makes a labyrinth – a maze to walk along. People would walk the maze while praying or meditating.
Learn by doing: find a labyrinth or draw one with chalk and walk it
Outside of Amiens cathedral
Bibliography and further reading about Amiens cathedral:
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.