I was in Europe earlier this month, adding to the list of Gothic cathedrals I’ve visited. I like the stained glass windows the best. Here is a small sample: a window from Chartres, a detail from Bourges, and a single pane from Bern:
You’ll notice I especially like the hell or judgment themed ones. Most windows are more pedestrian; I like more of an element of the fantastic. And even if hell, devils, and the day of judgment are damnable doctrines, they’re pretty good for fantastic and fearsome art.