OT, but I've discussed Gothic cathedrals with Gemini, and we don't make 'em like we used to--charitably, because they take up a lot of space? A Gothic cathedral looks like a bird with massive wings. Those "wings" are outside of the church's interior; people call them "flying buttresses"--they stop the walls from bursting outwards.

Then again, I wonder whether the modern innovation of using steel under tension could enable us to make the "wings" (buttresses) smaller.