While Rafael and the driver—whose name turned out to be Hector—made small talk, I stared out the window. We were nearing the heart of Tenochtitlán now, and the downtown core was dotted with what looked like Aztec pyramids. The stories of these gigantic government buildings were stacked layer upon layer like a squared-off wedding cake and seemed to be made of massive sandstone blocks, trimmed with gleaming copper. At street level they had the usual collection of doors and windows, but the higher levels were fronted by gigantic sculpted heads of what I could only assume were ancient Aztec gods or rulers. Goggle-eyed monstrosities alternated with leering serpent heads and skulls decked out in feather headdresses and ear plugs.