National Geographic: Nazi Megastructures: Series 1 (2013)

In their quest for world domination, the Nazis built some of the biggest and deadliest pieces of military hardware and malevolent technology in history. With total European military supremacy as their goal, they built defensive bunkers, impenetrable submarine pens, even a 'land battleship' weighing 1,000 tons. In six mesmerizing episodes, Nazi Megastructures uncovers the hidden remains of Hitler's most ambitious inventions, telling the stories of the engineering geniuses that designed them to fulfill Hitler's megalomaniacal demands, and revealing how these structures sparked a technological revolution that changed warfare forever.