The cathedral of Rouen was the first of the great French cathedrals.  This is, therefore, the prototype for all the other gothics, and as hard as they tried, few later got it as right as the original.  This church is drop-dead beautiful -- high, bright, airy, long vistas [a232], wide aisles, and breathtaking stained glass (what's left of it).  The sanctuary was hit by Allied bombs during the war.  The bombs took out several columns, collapsed some of the roof, and did miscellaneous damage all over the place.  Many of the windows did not survive and they were replaced by plain glass as a reminder of the cost of war, but the structure itself has been restored to near-new condition.  I went snapshot-crazy here.  I have about 20 shots of the inside; if you want more, I'll send them on specific request.
In the center of this picture is the console for the organ with the main altar to the right.  A few minutes after this picture was taken a series of organists each stepped up and played a selection or two.  One of them played Bach's Toccata and Fugue; I had never before heard it in such a close-up-and-personal fashion and I was thoroughly impressed.  Besides being a beautiful church, the acoustics are remarkable.
Rouen is also the town where Joan of Arc met her end (5.30.1431).  There is a huge cross allegedly on the site of the stake and a very pretty modern church next to it.  You'll see it in [a245] and [a250].