National Geographic : 2011 Jan
• than just a stupendous pile of earth or a cere- monial site where scattered tribes congregated once in a while. Nearly everywhere they dug, archaeologists found homes---indicating that thousands of people had once lived in the com- munity---and many of these homes had been built within a very brief span of time. In fact, the whole city seemed to spring to life almost overnight around 1050, a phenomenon now referred to as a "big bang." People streamed in from surrounding areas, built houses, and quickly constructed the infrastructure of a new city---including several mounds with buildings on top and a grand plaza the size of 45 football elds, used for everything from sporting events to communal feasts to religious celebrations. Making the story even more interesting was the clear evidence of ritual human sacri ce. Ar- chaeologists excavating Mound 72, as they labeled it, found the remains of 53 women and one very high status man, as well as the decapitated re- mains of four men who may have been on the wrong side of some sort of authority. e discov- ery belied the common belief that American Indi- ans lived in egalitarian communities without the sorts of o en brutally maintained hierarchies that de ned many other civilizations. Was Cahokia an empire, like the Mesoamerican civilizations to the south? It was too soon to tell, but something spectacular had happened here, and it became clear this was a mystery worth trying to solve. Cahokia, the rst thing you've got to do is climb the 156 steps to the top of Monks Mound. From the at top of this colossus---with a footprint of 14 acres, it is larger at its base than the Great Pyramid of Khufu, Egypt's largest---you not only get a sense of how much labor went into its construction, but you can also understand why it might have been built in the rst place. From here you can survey Cahokia's domain: the vast oodplain known as the American Bottom, stretching from St. Louis to a long line of blu s three miles east e Life and Death of a City With abundant wildlife and fertile soil for corn and other crops, Cahokia's location was key to its success. A stable food supply allowed Cahokians to devote time and energy to ambitious building projects, specialized crafts, and ceremonies. So why did they abandon their city? One theory: The rain stopped falling.