What remains of past inhabitants of the jungles, lost cities, underground and underwater structures and their civilizations? The reminders of the Ancients are everywhere. They are preserved in remnants in archaeology. They are found in stories from mythology. Who were these people? Aliens, humans, or myths? How did they rise, fall, and will they rise again? From pyramids and underground bunkers to watery graves and ancient astronauts, Lost Civilizations explores the archaeological evidence left behind by more than 70 of these ancient civilizations.