Schwerer Gustav, or the “Heavy Gustav,” was the largest and most powerful gun used in World War II and was the heaviest piece of mobile artillery ever built. Its 7-tonne shells could breakthrough over 7-meters of reinforced concrete, but 500 people were needed to fire it, and about 4,000 more were required to protect and operate it on the battlefield... | Dark Documentaries

The Schwerer Gustav, the largest artillery gun ever constructed. Designed by the German arms manufacturer Krupp in 1934, this giant railway gun weighed 1,350 tonnes and measured 47.3 meters in length. Intended to devastate the Maginot Line during the invasion of France, it boasted an 80-centimetre caliber and could fire 7-ton shells over a range of 47 kilometres! | Simple History