Planned Ritual: Cahokia’s Monumental Causeways

Detailed examination of the Cahokia site through aerial LiDAR and ground reconnaissance has revealed additional features of interest in the vicinity of Rattlesnake Mound. These include a possible early Cahokian mound platform superimposed by the Rattlesnake ridgetop tumulus. In addition, another artificial causeway is now apparent tothe east of the foundational or great Rattlesnake Causeway. Similar to the primary example, this second raised earthen walkway appears intended to facilitate human processions through standing water, as we recently verified. In addition, the second great causeway shares the same elevation, width (about 20- meters), and alignment (to Cahokia’s documented 5 degree offsetgrid). In fact, it parallels the Rattlesnake Causeway for at least 300 meters. Taken together and pending ground truthing, all of the new features indicate a previously unrecognized degree of spatial complexity if not chronological depth involving monumental water features and centralized water rituals.