What does a city’s rooftops reveal about it?

I was flying over Lyon last week—just a low pass, not even on the chart—and I noticed how the rooftops weren’t just tiled or slanted. They had rhythm. Like someone had laid out a pattern across the whole city, almost like a map of memory. It made me wonder: what if you could read a city the way we used to read terrain? Not by roads or names, but by how the roofs rise and fall. Are we losing that kind of quiet language? Or is it still there, just ignored?