The Mayans were not a city-state but a megalopolis connected by causeways and canals.
Latest LiDAR maps show the Mayan world probably had upwards of 20 million people and an agricultural capability rivaling what California produces today. The Mayans were not a city-state but a megalopolis connected by causeways and canals. Couple this with their language, art, math, and astronomy, and the Mayans belong with the Chinese, Egyptians, etc. Amazing stuff, really.