A vast number of man-made mounds have been identified across the Lower Mississippi Valley in North America, spanning across incredible distances. To this day however, a great mystery surrounds this sudden burst of earthwork constructions set to have happened over 5,000 years ago and dating as far back as 8,000 years ago. At a time where native American cultures and hunter-gatherer societies were believed to only rely on primitive behavior, the world’s largest effigies and mounds arose in precise alignment with celestial references and events.