Hitler sure had some grand ideas—from mass murdering Jews and conquering Europe, to rebuilding Berlin and draining the Mediterranean sea. Even when generally showing off how great Nazi Germany was, the Führer and his generals liked to do things in style. They even built what would have been the world’s biggest hotel, but the project had to be called off because there were more pressing matters at hand, such as invading France.
In the 1930s, France constructed a series of massive fortification and obstacles called the Maginot Line to protect the country against invasion from the east. These fortifications were some of the strongest in existence at the time with deep underground bunkers, state-of-the-art retractable turrets, infantry shelters, barricades, artillery and anti-tank gun emplacements and so on. Nothing the German Wehrmacht had in their armory was capable of penetrating this formidable defense. So Hitler went to munitions maker Krupp for a solution.
Adolf Hitler (second from right) and Albert Speer (right) inspecting the 800 mm Gustav railway gun in the year 1943.