From crop circles to massive petroglyph formations, Erich von Däniken reveals the signs that suggest advanced beings have had a long-term presence upon Earth. In ancient times, when the gods walked among us, they left their mark scrawled upon the Earth. As these extraterrestrial beings scoured the barren landscapes for their needed resources, primitive human civilizations did their best to emulate the markings left behind from advanced technology. This may be the primordial cause for phenomenal sites such as the Nazca lines in Peru. As we traverse through modern times, could these gods still be leaving us signs of their existence through the widespread appearance of crop circles?