This intersection is the point from which the entire logic of the city becomes apparent. Multiple lines of evidence suggest that the two great avenues were not laid out following the terrain or the water routes, but following the stars and their movement. The Avenue of the Dead points toward the horizon where the Sun sets on the days it passes directly overhead—a phenomenon that occurs twice a year at this latitude, and that in the Mesoamerican calendar marked the beginning and end of the agricultural cycle. The East–West Avenue points precisely toward where the Pleiades disappeared on the horizon at the time of the city's founding. From this point, the three great pyramids align in the landscape with a precision that is anything but accidental. At Teotihuacan, nothing is.