Secrets of the Underground S2, E5

Using cutting-edge technologies such as ground penetrating radar (GPR), LIDAR (Light Detection and Ranging), and 3-D imaging, scientists research fascinating underworlds of secret tunnel networks, ancient structures, and bizarre geological occurrences that offer glimpses into our history.

Cast:Rob Nelson , Stefan Burns , Tim Bechtel , Adam Cho , Jared Peacock , Valerie Van Heest , Tracy Beach , Bradley T. Lepper , Brent Breithaupt , Griffin Alberti , Janet Watt , Jennifer Burnham , Larry Johnson , Tim Kilgannon , Aubri Jenson , Luther Strayer , Dale Rucker , Frank Watson