There is that ruin that was actually a spaceship.
See the documentary “Kingdom of the Crystal Skull”.
sounds like you need to bone up on your archaeology. Two good books here are 1493 and 1491. both books are by Charles Mann. The first book covers what the author Charles Mann describes as the columbian exchange. This is the movement of everything from diseases to plant species to people to animals to the new world and everything from potatoes to tomatoes and silver to the old world. The writing style is very readable. 1491 compiles all the research of the last 30 years to give a very full picture of pre columbian America. The most interesting thing about that world is that from the jungles of Brazil to the north eastern forests of the US—the Indians managed the forests to produce crops—and had done so for 1000 years or more.