The architecture is absolutely amazing, but they have a law or city ordinance that doesn't allow new construction to exceed a certain height because they don't want the tall skyscrapers to dwarf the older buildings. While the buildings aren't much taller than 8 stories, the city itself is very compact, to the point of feeling crowded. Space is at a premium and all the rooms and stores are quite small. They pack a lot into each space.
Parking is almost nonexistent so everyone rides bikes, mororcycles or they walk and walk we did. Everywhere. They have an amazing subway system but even so you have to walk down lots of stairs to make the connection you want. Needless to say, I came home well toned.
We saw so much that I'm on visual overload, but my two favorite areas was Monet's home and water gardens and Chambord Chateaux.
Oh and the Reims Cathedral was breathtaking. The heighth was astounding, but the solemn atmosphere was spiritually uplifting.