In the late 1930s, Adolf Hitler was determined to conquer France – so determined that he ordered the development of the biggest gun the world has ever seen, which was capable of wiping out cities with just a few shells. Shortly after the turn of the decade, the super-gun, named the Schwerer Gustav – or Great Gustav in English – was completed. The 1,350 tonne machine is still the biggest weapon ever built and was capable of firing town-levelling 10 tonne shells more than 30 miles. The Schwerer Gustav and was designed to smash the French Maginot Line – an line of massively reinforced concrete gun emplacements along the north east of France, conceived after the German invasion of France in 1914.

NC The Schwerer Gustav weighed 1,350 tonnes

The line was designed to be an impregnable buttress on the France German borders met. However, late complications in the development of the Schwerer Gustav, which required days worth of track laying to make it mobile and thousands of soldiers to operate, meant that the destructive arsenal was not ready for the Battle of France and anyway the German military simply went around the back and outflanked the Maginot Line and head to France through Belgium.

GETTY A fortress on the Maginot Line

Crucially at this point the weapon was turned around and headed towards the Eastern Front, where Nazi Germany was engaging in battle with the Soviet Union. After making its way to the Crimea on a 25 car train, the Schwerer Gustav was used in battle for the first time, showcasing the devastation that it was capable of. For four weeks the weapon was being fired at Russian forces, penetrating 100 feet underground to obliterate supposedly impregnable below-the-surface Soviet ammunitions store.

GETTY Adolf Hitler originally ordered the construction of the gun for the Battle of France

Eventually the Soviets surrendered under heavy fire and it proved to be one of the last actions taken by the Schwerer Gustav, with German forces allegedly destroying it towards the end of the war as to make sure the allied forces could not get their hands on it following the then inevitable defeat of the Nazis. However, things could have turned out extremely differently.

NC Adolf Hitler's super-gun; Schwerer Gustav

If Hitler’s army had acted more quickly in completing the machine and it was used in the Battle of France, the Nazis could have easily manoeuvred the machine through France to Cap Gris Nez – the closest point to England. There, and with a firing range of 30 miles, the Schwerer Gustav was more than capable of bombarding the heavy fortifications in the south east of England.

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