Just east of the San Francisco Bay Area are the Berkeley Hills Walls--remnants of a massive, stone wall that stretches a distance of over fifty miles. The wall segments are up to six feet high in some places and are constructed of tightly fit limestone boulders. Scott is in intrigued by the fact that nobody knows who built the wall or even what purpose it serves. The only historical precedent for a miles-long, manmade, ancient wall is the Great Wall of China. Could ancient Asiatic explorers have made it all the way to the North American West Coast? In investigating the theory, Scott uncovers other evidence that could suggest the Chinese with their massive maritime fleet made it to the New World, using maps that were in the possession of Kublai Khan. He also discovers evidence that European explorers knew about China's epic voyages, including Italian explorer Marco Polo.