When Columbus stepped ashore in 1492, millions of people were already living in America. It wasn't exactly a 'new world,' but an old one whose inhabitants had built a vast infrastructure of cities, orchards, canals, and causeways. After Columbus, an endless wave of explorers, conquistadors, and settlers arrived, and with each of their ships came a Noah's Ark of plants, animals, and disease. Here is an exploration into the mysterious world of ancient American history.

Originally broadcast as a television program on the National Geographic Channel. Features: Columbus landfall.