The Tower of Babel is one of the most famous stories of the Bible, and to find out if it really existed, archaeologists use cutting-edge tech and the latest science to investigate how ancient engineers could have built such an extraordinary megastructure.

The long-lost underground bunker of Adolf Hitler is home to some of the greatest secrets of the Nazi regime, and now, experts use cutting-edge tech to discover new evidence of Hitler's evil vision for global domination. The bunkers reviewed are the Führerbunker in Berlin, the Wolf's Lair in eastern Poland, and Project Riese (The Giant) under Książ Castle in southwestern Poland.